Probiotics: What Do These Bacteria Do?

by Nusheen Orandi

When I’m shopping in the dairy aisle of the grocery store, I stand in front of the yogurt section for a while. When did it get so huge? Greek, Icelandic, Kefir, whole milk, low-fat, non-fat, goat’s milk, and coconut milk are all options. What’s making yogurt so popular? Well, its probiotic nature is one of its claims to fame.

What does probiotic mean?

“Probiotic” describes anything that stimulates the growth of microorganisms in large enough numbers to enhance health. With food, this involves bacteria and yeast that ferment products we love, like beer, yogurt, and cheese. With health, the primary interest lies with gut microflora. Gut microflora affects health and digestion in a number of ways including food intolerances, food allergies, and other forms of gastrointestinal discomfort. This not only sparks nutrition research interests but food industry interests as well, who try to market the “functional foods” that could enhance health.

What makes yogurt so special?

The making of yogurt involves probiotic bacteria. Starter cultures begin the process of fermenting hot pasteurized milk to make yogurt. These starter cultures are bacteria not found in the intestinal tract that include Streptococcus thermophilus and L. delbrueckii ssp. Bulgaricus. However, other bacteria used in yogurt-making are found in the intestinal tract, such as members of the Lactobacillus and Bifidobacterium species. Because these bacteria are also found in the intestinal tract, they are known as “dietary adjuncts.” The bacteria in yogurt produce lactic acid, which reacts with milk protein to give it the creamy texture and tart taste. These bacteria’s ability to be produced in high amounts, withstand long shelf life, and benefit human health give yogurt’s its probiotic reputation.

What are the health benefits of probiotics?

Should we eat another bowl of yogurt or a second pint of Guinness? Microbiology experts think so. Scientific evidence points to many health benefits including anti-microbial activity, anti-diarrheal function, enhanced immune function, and improved lactose intolerance and gastrointestinal function.

Anti-microbial activity

Probiotic bacteria produce organic acids that suppress the multiplication of pathogenic bacteria like E.coli and salmonella, which can make us sick. The increased acidity of the intestinal tract enables this function.

Lactose Intolerance

People who experience discomfort from dairy products due to lactose intolerance can sometimes tolerate yogurt due to the probiotic bacteria. People with lactose intolerance lack sufficient amounts of the enzyme lactase in their intestine. Without enough lactase, people inadequately digest the milk sugar. The probiotic bacteria in yogurt contain an enzyme called b-D-galactosidase that partially digests the lactose in yogurt, making it easier for lactose intolerant people to eat yogurt comfortably.  Research also suggests that probiotic bacteria can enhance lactase activity.

Anti-diarrheal Function

Pathogenic bacteria and antibiotic use can cause diarrhea. Probiotic bacteria compete with diarrhea- causing pathogenic bacteria on epithelial cells in your intestine, which reduces the likelihood of diarrhea. Probiotic bacteria especially help people required to take a lot of antibiotics. The antibiotics reduce the amount of “good” microorganisms in your intestine, which can causes diarrhea symptoms. Probiotics help re-colonize the intestine with these “good” bacteria to improve intestinal movement. Hospitalized people who take a variety of medications may benefit from certain probiotic bacteria.

If probiotic bacteria are so good, should we add more to foods?

Because of the noted benefits of probiotic bacteria, debate surrounds the idea of adding more probiotic bacteria in addition to the ones found in traditionally made yogurt and other fermented products. One example is Activia brand yogurt. Probiotic bacteria are available in powders, capsules, and tablets. However the type, amount, and ratio of added probiotic bacteria remain unclear. Clinical trials raised discussion about whether probiotic bacteria given to infants could decrease food allergies later in life. However, further studies provided inconclusive evidence.

Probiotic bacteria not only help make the food we love, but help our bodies know what to do with it! Although those with dietary restrictions or illness may benefit from added probiotic bacteria, the probiotic bacteria found in our foods may be enough to give the rest of us the potential benefits. It just gives us another reason to maintain a well-balanced diet.

Nusheen Orandi is a first-year student from California in the Nutrition Communication program and likes to spend her time tea-shop hunting, tensely watching the Tottenham Hotspurs, and cooking and eating with friends and family.

How Does a Ketogenic Diet Affect YOU? Part 3: C-Reactive Protein: A Marker of Inflammation

by Katie Mark

The latest craze surrounding the ketogenic diet has us further investigating whether or not a high-fat/low-carbohydrate lifestyle might be an appropriate dietary approach for some people. In this 3-part series (click here for part 1 and part 2), we’re evaluating how the ketogenic diet affects biomarkers.

The ketogenic diet is a very low-carbohydrate (<10% of total calories), moderate protein and high-fat (>70% of total calories) diet. After at least two weeks of keto-adaptation, the body’s energy source switches from glucose to fat.

In part one of “How Does a Ketogenic Diet Affect YOU?” we found studies suggesting that nutritional ketosis lowers fasting glucose and insulin levels and possibly increases insulin sensitivity. In part two, we investigated the impact of ketosis on cortisol. We found that a high-fat, carbohydrate-restricted diet may increase certain forms of cortisol, but blood cortisol levels are only half the story. Further research is needed to clarify the relationship between ketosis and an increase in certain forms of cortisol: the active form (cortisol), the inactive form (cortisone) and metabolites of cortisol from enzymatic breakdown.

Now let’s evaluate how the ketogenic diet affects C-reactive protein (CRP).

Increased CRP: Is there a need to worry?

C-Reactive Protein

C-Reactive Protein Model

CRP is considered a marker of inflammation. The liver makes CRP when inflammation in the body is present. High levels of CRP are influenced by genetics, high stress, exposure to environmental toxins and a sedentary lifestyle. Diet can also impact CRP levels, especially diets high in refined and processed foods.

There are two blood tests to measure CRP. The non-specific test indicates acute CRP levels that result from general inflammation in the body. The more sensitive measure is the highly sensitive CRP (hs-CRP) test, which accurately measures basal levels of CRP by measuring inflammation in blood vessels. The hs-CRP test is the accepted measure to determine the risk for cardiovascular disease (CVD).

Higher CRP levels signify a higher risk for developing CVD and abdominal obesity. Weight loss is known to decrease markers of inflammation such as CRP.

It is believed that a high saturated fat and very low carbohydrate diet (VLCARB) increases the risk for CVD. A study published in Nutrition Metabolism (London) compared a VLCARB diet to two low saturated fat, high carbohydrate diets to determine their effect on body composition and CVD risk. The isocaloric (similar calorie composition) diets were: very low fat (CHO:fat:protein; %SF 70:10:20), high unsaturated fat (50:30:20; 6%) and VLCARB (4:61:35, 20%). The study concluded that weight loss resulted in a reduction of CRP regardless of the dietary macronutrient composition. Yet, it is uncertain whether or not the macronutrient composition of a diet influences inflammation.

A study published in The Journal of American College of Nutrition found an increase in CRP in overweight women who followed a short-term low carbohydrate, high-fat weight loss diet. The study reported that an increase in CRP might have resulted from the oxidative stress caused by this type of diet.

Another study published in Obesity (Silver Spring) looked into the inflammatory response caused by a high-fat, low-carbohydrate weight loss diet (HF) by randomly assigning 19 overweight men and women to either an antioxidant (AS) or placebo (P) supplement. The objective was to see if the antioxidants vitamins C and E could decrease the inflammation reported in a HF diet.

CRP decreased 32% in the AS group and increased 50% for the P group; however, this was statistically insignificant. The HF diet did not decrease CRP within the short-term 7-day study even though other markers of inflammation decreased.

The study could not confirm if oxidative stress was causing the inflammation. It was concluded that further research is needed to determine the different CRP responses over the long term, especially while using antioxidant supplements. This is important considering most fruits and vegetables, which are low in fat, contain antioxidants.

The Verdict

A ketogenic diet may increase CRP levels, but weight loss reduces CRP levels. The reason for the increase in CRP is unclear. One plausible explanation is that low intakes of magnesium, vitamin C and other nutrients while on a ketogenic diet may lead to this effect. When magnesium is low, CRP increases. It has been reported that increased vitamin C intake may reduce high CRP levels.

An imbalance between anti-inflammatory fats (omega-3 fatty acids) and pro-inflammatory fats (omega-6 fatty acids) is another possible explanation. Polyunsaturated vegetable oils primarily contain the pro-inflammatory omega-6 fatty acids. Eating less grain-fed meats and chicken and more grass-fed meats and free-range chicken is also important to consider. Grain-fed animals have higher omega-6s whereas grass-fed animals have higher omega-3s. Omega-3s are anti-inflammatory and important for normal body functions, including regulating blood clotting and building cell membranes in the brain. Omega-3s are also suggested to protect against heart disease.

An elevated CRP level is never a good thing. If you are opting for a ketogenic diet, increasing magnesium and vitamin C intake as well as choosing grass-fed products may reduce CRP levels.

Katie Mark is a first year Nutrition Communication/Master of Public Health student who enjoys road cycling and traveling.

How Does a Ketogenic Diet Affect YOU? Part 2: A Deep Look Into Cortisol

by Katie Mark

Recent high hopes for high-fat diets have us further evaluating the ketogenic diet for a wider population. In this three-part series, we’re examining how the ketogenic diet affects biomarkers. Part 1 of this series investigated what ketosis does for fasting glucose and insulin. In Part 2, we look at how a ketogenic diet may affect cortisol levels.

High-fat…high cortisol…high stress?

Cortisol is considered the “stress hormone,” and it influences blood sugar levels, blood pressure, immune response, and stress response. Chronically elevated levels of circulating cortisol can hinder cognitive performance, disrupt sleep, impede immune function, increase abdominal fat, and cause blood sugar imbalances.

Studies have found that cortisol levels increase on a ketogenic diet, but some say the relationship between ketosis and high cortisol needs to be made clearer. First, chronically elevated cortisol correlates with metabolic syndrome, a group of symptoms such as high blood sugar, excess abdominal fat, and abnormal cholesterol levels that increase the risk for diabetes, heart disease, and cancer.

It seems possible that ketogenic diets may cause metabolic syndrome because higher cortisol levels suggest the onset of metabolic syndrome. However, this isn’t the whole picture: It’s also possible that there are multiple forms of cortisol, and their measurements mean different things.

Cortisol is measured in bodily fluids, including urine, saliva, and blood. Multiple forms of cortisol are measured from these samples: cortisone (the inactive form), free cortisol (the active form), and metabolites of cortisone and cortisol resulting from enzyme activity. Equally important, these levels of cortisol biomarkers can vary depending on the time of day.

A holistic understanding of cortisol metabolism relies on looking at the enzymes 11β-hydroxysteroid dehydrogenase (11β-HSD) and 11β-HSD1 (a subtype of 11β-HSD). 11β-HSD1 is found in every cell, but the highest amounts are found deep within fat cells. In fact, it does not matter if a person’s blood cortisol level is low, medium, or high because a highly active 11β-HSD1 will generate a high amount of cortisol inside cells.

Here is a breakdown of cortisol metabolism:

  • Production: 11β-HSD converts cortisol (active) to cortisone (inactive)
  • Regeneration: 11β-HSD1 converts cortisone to cortisol
  • Clearance: Other enzymes help metabolize cortisone and cortisol into metabolites

The cortisol profile of metabolic syndrome, which the ketogenic diet reverses, consists of:

  • High cortisol production
  • High cortisol clearance rates
  • High 11β-HSD1 expression in adipocytes and low 11β-HSD1 expression in the liver (the location that determines where and when cortisol is regenerated)

Now, let’s see how a 24-hour urine proxy is used for detecting cortisol. This proxy results in a less-than-clear picture because cortisol levels are affected by production, regeneration, and clearance. For instance, if clearance decreased or if regeneration increased, cortisol levels could go up if production stayed the same or lowered. This is analogous to simply measuring someone’s total cholesterol without observing LDL and HDL.

Take home message: levels may appear similar when there is a big difference in cortisol metabolism.

One study, published in The Journal of Clinical Endocrinology and Metabolism, used 17 obese men and randomly assigned them to an ad libitum (eat as much as you want) high fat-low carbohydrate (HF-LC) diet (66% fat, 4% carbohydrate) or moderate fat-moderate carbohydrate (MF-MC) diet (35% fat, 35% carbohydrate) for four weeks.

The study found a reversal of the previously described metabolic syndrome cortisol profile for only the HF-LC group: blood cortisol increased, clearance decreased and regeneration increased (due to an increase in 11β-HSD1 activity in the liver). According to the researchers, the ketogenic diet improved the cortisol profile because it was different from the cortisol profile seen in metabolic syndrome.

Furthermore, even though the MF-MC group lost a similar amount of weight, there was no change in 11β-HSD1 activity. This increase in 11β-HSD1 activity in the HF-LC group was independent of the differences in energy intake and weight loss because the same effect was seen in the controls.

A final component to note is that obesity is associated with high cortisol. However, the connection between obesity and elevated serum levels of cortisol has not always been a consistent connection.

Some people with high stress and lots of abdominal fat had normal or low levels of cortisol in their blood. Usually, chronically elevated levels of cortisol leads to increased adiposity; yet, there have been cases of people with high stress and high cortisol, but no obesity. And as we saw in “The Basics of the Ketogenic Diet,” the ketogenic diet has demonstrated effectiveness as a weight loss tool.

What’s the verdict?

We see that diet, especially a carbohydrate-restricted one such as the ketogenic diet, may increase certain forms of cortisol. But blood cortisol levels are only half the story—cortisol levels inside cells illustrate the other half. Also, cortisol will vary depending on the time of day, with levels highest in the morning. Caffeine, stress, and exercise can also increase cortisol levels.

Ultimately, further research is needed to better understand the connections as to why cortisol increases on a ketogenic diet and if cortisol levels are more affected by other variables, such as the activity of the 11β-HSD1 enzyme.

Katie Mark is a first year Nutrition Communication student from Miami, Florida. Due to Boston’s Snowpocalypse, she does not foresee herself living in Boston in the future, so she will return to South Beach following graduation.

How to Become an Expert Gum Taster: My Experience as a Sensory Scientist at Wm. Wrigley Jr. Company

by Disha Gandhi

Warning: the following article requires active participation. Please have 1-2 pieces of gum at your side prior to reading.

The multibillion-dollar food industry provides us with all of the calories and food products we desire. But who within the food industry conceptualizes the vast variety of foods available? Who develops the recipes, evaluates consumer response, and assesses the quality? Food scientists, that’s who.

Prior to working as a food sensory scientist at the Wm. Wrigley Jr. Company, I completed my undergraduate degree in Food Science at the University of Illinois. In fact, most graduates within my program went on to work throughout the food industry. But when we learn about optimal nutrition at the Friedman School, the food industry, creating products for profit, is often positioned as at odds with a healthy diet.

We learn about reducing sodium intake, avoiding processed foods, and returning to the way our grandparents ate. It may seem like food scientists are the monsters that invented and feed the obesity and diabetes epidemics. Though we can argue that this notion seems pretty reasonable, food scientists and their industries do exist and we need them for many reasons.

Believe it or not, the guy who invented gum, William Wrigley Jr., was a food scientist back in 1891. Without his invention the person pushed up against you on a very crowded train would probably have very nasty breath. So in honor of Wrigley, let’s have some fun! Grab those pieces of gum and work through the following:

In answering these four simple questions, base your responses on the following 9-point hedonic scale test:

1-Dislike Extremely
2-Dislike Very Much
3-Dislike Moderately
4-Dislike Slightly
5-Neither Like nor Dislike
6-Like Slightly
7-Like Moderately
8-Like Very Much
9-Like Extremely

Question #1. On a scale of 1-9, please evaluate the overall liking of the gum:
1 2 3 4 5 6 7 8 9

Question #2: On a scale of 1-9, please evaluate the overall liking of the flavor of the gum:
1 2 3 4 5 6 7 8 9

Question #3: On a scale of 1-9, please evaluate the overall liking of the texture of the gum:
1 2 3 4 5 6 7 8 9

Question #4: Continue chewing the gum for roughly five minutes. Please evaluate the overall liking of the flavor intensity of the gum:
1 2 3 4 5 6 7 8 9

Congratulations! You just completed a mini consumer sensory test questionnaire. During my year at Wrigley, my group conducted a number of consumer tests on various Wrigley and Mars products such as Orbit Gum, 5 Gum, Skittles, Starbursts, Snickers Ice Cream Bars, Uncle Ben’s Rice Products, amongst others. We evaluated consumers’ preferences on different scales similar to the one you just completed. Thereafter, we delivered the results to Wrigley’s head sensory scientists who were better able to make decisions regarding their formulations, eventually deciding whether or not the tested product should be released into the market.

Now that you’re aware of how sensory testing occurs, here’s some insight into what I did as a food scientist:

What was a really cool product I worked on?
I definitely have to say that it would be Dove chocolate-covered gum. I had never thought that gum could be covered in chocolate! Not only did the food scientists create gum with a chocolate coating around it, they also created raspberry, chai, and strawberry coated gum. Some formulations tasted very well, while some were vomit-inducing. This product was released to select Dunkin Donuts around the Chicago area. I worked on this product in its early stages, so it might be a while before it gets released nationwide, if at all.


What was so great about this job?
When you work in research and development, you tend to know a lot of information about the projects that pertain to your team. I was lucky with my position because I was exposed to a whole variety of products that both Wrigley and Mars produced including products from around the world, such as Chinese jasmine flavored mints

My team did not only do consumer acceptance tests, we also did qualitative descriptive analysis. So how does this work?
First, here is a list of basic tastes, flavors, and textures:

Screen Shot 2015-02-28 at 8.29.05 PM

Now, let’s go back to that piece of gum you were/are chewing. Or, if you have another piece handy then start chewing it.

Now ask yourself: after about 30 seconds of chewing the gum, what were the range of flavors you experienced and at what intensity would you rate these flavors on a scale of 0-15? 0 represents no flavor intensity and 15 represents a very high intensity. How about after a minute? What about 12 minutes?

Qualitative descriptive analysis is performed by panelists who evaluate the basic tastes, flavors, and textures each on a scale of 0-15. What was really interesting about these panelists is how they were equally calibrated regarding gum and candy. For instance, a sweetness rating of five represents the sweetness level of 50 grams of sugar in 1L of water. They were given this reference sample daily to ensure their internal calibration was set. Panelists then were able to evaluate the sweetness of a piece gum or candy by referring back to their reference sample. For your general knowledge, the sweetness of a piece of gum starts at an intensity of about 8-9 and as time progresses it lowers to about a 2. So, in the exercise earlier, if you rated the sweetness of your gum at about 8-9, you are already on your way to becoming an expert gum taster! Scientists looked for consistency in the panelists’ ratings of each flavor attribute in order for them to discern the flavor profile of their product. This knowledge helped them decide for example, if a different type of sweetener in Orbit Spearmint Gum made a difference when compared to the control product.

Valuable exposure to sensory science, working with a variety of people, and now knowing almost everything there is to know about gum (except how it’s formulated) made working for Wrigley a wonderful learning experience.

Though Disha Gandhi thinks that sensory science is neat and vital for a company’s well being, her heart lies in food and nutrition. Hence, why she’s studying towards a MSc in Biochemical and Molecular Nutrition at the Friedman School. In her free time she loves to read food blogs and explore restaurants in Boston.

Bulletproof Coffee: the Breakfast of Champions?

by Ally Gallop, BSc, RD, CDE

Imagine waking up in the morning to a breakfast of butter, oil, and coffee. Better known as Bulletproof Coffee, it’s the new rage in the diet world. With proponents noting marked improvements in alertness, hunger suppression, and weight loss, bulletproof coffee and its creator are altering the morning routine. But navigating through these claims, the science doesn’t align.

After a trip to Tibet in 2004, Silicon Valley businessman Dave Asprey tasted Tibetan Yak Butter Tea: a concoction of brewed tea, salt, and yak butter. Upon returning to the U.S., Asprey devised his own version. Now marketed as bulletproof coffee (or BPC), it pairs well with his newly released book The Bulletproof Diet. Advocates for BPC include U.S. Olympic marathoner Ryan Hall, Divergent actor Shailene Woodley, and singer/songwriter Ed Sheeran. BPC is said to be creamier than a latte, prevent hunger before lunch, increase alertness, and be loaded with vitamins A, E, and K2 alongside omega-3 fatty acids. Yet the most enticing reason in opting for this drink is because it seemingly causes weight loss without having to exercise.

The recipe for BPC is simple. In a blender combine many of Asprey’s own products:629px-Bulletproof_Coffee_Starter_Kit

  • At least 2 tablespoons of unsalted grass-fed butter,
  • 1-2 tablespoons of Brain Octane™ Oil, and
  • Bulletproof® Upgraded™ brewed coffee beans.

Keep in mind, BPC is meant as a breakfast replacement. So let’s compare the BPC nutritional content to that of a typical breakfast: two scrambled eggs, an apple, black coffee, and a slice of whole grain toast with a tablespoon of peanut butter.

Typical Breakfast BPC *Unable to find specific nutrient data for grass-fed butter and omega-3 content.**The USDA Foods List only lists information for vitamin K1.
Calories (calories) 491 461
Total Fat (g) 23 51
Saturated Fat (g) 4 43
Omega-3 Fatty Acids (mg) < 1 n/a*
Total Carbohydrates (g) 48 0
Total Fiber (g) 10.4 0
Protein (g) 24 0
Vitamin A (IU) 803 400
Vitamin E (mg) 1.88 0.4
Vitamin K1 (μg) 9.5 0.8
Vitamin K2 (μg) n/a** n/a**
Caffeine (mg) 142 142

Starting the day off with a high-fat brew that shuns hunger and enhances alertness sounds like a great idea. Losing weight is easier when your stomach isn’t grumbling. High-fat BPC in the gut slows the rate of stomach emptying, suppresses ghrelin (the “eat more” hormone), and reduces the amount of calories consumed at subsequent snacks and meals. Since fat takes the longest to leave the stomach and be digested, even in its liquid form, Asprey’s claim makes some sense.

But Asprey’s claims regarding omega-3s and vitamins A, E, and K2 are cloudier. The amount of these nutrients in grass-fed versus conventionally grain-fed beef is higher. Yet only 60% of studies found a statistically significant difference. Further, no research exists on the amount of omega-3 fatty acids in butter- all the research comparing omega-3 contents is in types of beef, not dairy.

Recently, I contacted Kerrygold, a popular brand of grass-fed butter, and asked them to elaborate on the omega-3 content their product. They responded by saying that they have no research on omega-3’s present in butter. While grass-fed dairy may be a wiser nutritional source, there is currently no research that supports Asprey’s supposition that it has more omega-3s.

The caffeine content of BPC is likely the source of increased alertness drinkers report. It’s also possible that if the coffee truly does have a higher omega-3 content, those omega-3s could give the brain extra power.

Asprey’s line of Bulletproof® Upgraded™ coffee beans are touted as being free of mycotoxins (i.e., mold), which he claims are pervasive components of every other coffee on the market. However, coffee producers like Starbucks and Dunkin Donuts have long known about these mycotoxins. That’s why coffee beans are wet-processed, which means that the beans are washed to eliminate the mold. So the upgraded brew is no better than the rest.

But what really stands out about BPC? How about its fat content: the brew fulfills 23% of both your daily total caloric and fat intake. The Institute of Medicine (IOM) recommends 25-35% of daily total calories should come from fat. BPC fulfills that quota on its own. The Canadian Society of Intestinal Research also reminds us how fat is a stimulant for the intestines. Higher intakes may result in abdominal cramping, diarrhea, and floating stools. But that’s never advertised.

Being so high in calories, how can BPC help weight loss? If, like with any diet, fewer calories are consumed, then weight loss may occur. Asprey’s book recommends following a low-carbohydrate diet as to induce ketosis. And food restriction generally leads to weight loss.

In an interview with Runner’s World, University of California Davis’ director of sports nutrition Liz Applegate debunks Asprey’s idea behind Brain Octane™ oil, which is made of medium-chain triglycerides (MCTs). Asprey believes that the oil increases the body’s ability to burn calories because it is processed differently than other fats. Unlike long-chain triglycerides, MCTs pass directly from the gut into the bloodstream and are immediately available to be burned for energy. However, Applegate notes that there is no scientific evidence to support MCTs’ ability to increase metabolism and promote weight loss. If consumed in amounts that surpass the body’s immediate needs, MCTs will still be converted to and stored as fat.


Breakfast of Champions?

Ultimately, this article wouldn’t be complete without attempting BPC myself. I found it odd watching butter dissolve into my morning cup. The oil slick on top was definitely unsettling. Using coconut oil and regular coffee in place of Asprey’s oil and beans, the concoction was creamy with a subtle hint of coconut. My hunger was suppressed the rest of the day, cravings for carbs were reduced, and I was able to forgo my mid-morning snack. In comparison to my normal routine of breakfast and a snack, I likely saved 120 calories. But due to an injury, I was unable to exercise. Would this daily pattern of high-fat BPC power me through morning exercise sessions?

Should YOU add BPC to your diet?

The typical breakfast provides protein and fiber, long having been touted as essentials for their hunger-suppressing properties. But choose BPC, and neither exist. The idea is you can’t have both food and BPC.

For those who already eat breakfast, replacing it with BPC on a short-term basis or intermittently could be all right. The BPC’s calories are appropriate for a morning meal. Caloric intake may even be less, depending on what one would normally eat. However, the habit of drinking coffee alongside breakfast may return, thereby increasing total calories consumed. In a recent article, Chris Gayomali, a journalist for Fast Company, tried BPC for two weeks. By the end, he was adding toast in addition to his BPC. After two weeks he ditched BPC completely because he missed eating solids.

Diet trends tend to fail due to deprivation. Given that all other meals and snacks consumed throughout the day remain constant, having BPC and food in the morning could lead to weight gain since it is so high in calories.

If you’re adamant about BPC, doing so every-other-day and ensuring intake of higher fiber and protein foods is advised. That way you can indulge while still limiting saturated fat intakes, promoting gut health with fiber, and sparing protein. Following the IOM guidelines, you wouldn’t require any additional fat on a BPC day. On those days opt for vegetable-dishes, lean protein, and unsaturated fats, like those from nuts, plant oils, and avocados.

For those who don’t typically eat breakfast, adding almost 500 calories of BPC in addition to your usual food consumption could lead to significant weight gain.

So what’s the final consensus?

When it comes to Bulletproof Coffee, the science is lacking. Egregious claims that the oil supplies “fast energy for the brain,” “reduces brain fog,” and is responsible for “rebalancing…yeast in the gut” are stated on Asprey’s website. Yet they lack any footnotes for supporting literature.

We also can’t look at foods in isolation. Rather, the whole diet matters. Asprey’s BPC argument focuses on the nutrients in two items: butter and oil. Humans are encouraged to seek variety in the foods we eat. The typical breakfast I detailed above already contains all of the nutrients advertised as part of BPC and more. If for an entire month one were to replace their breakfast with solely BPC they would be missing out on vital nutrients that variety would fulfill.

Like any other diet, BPC is supposedly “universal.” It’s meant to meet the needs of all of its followers. For me, I felt full. Others may be starving after just a couple hours.

And ultimately, Dave Asprey is a businessman. His empire includes a line of pricey oil and coffee beans in addition to travel mugs, T-shirts, and anti-aging skin creams. With a booming business plan, book, and BPC shops in the works, Asprey is raking it in when you drink his breakfast of champions.

Ally Gallop, BSc, RD is a Certified Diabetes Educator and is studying towards an MS/MPH focusing in health communication and epidemiology. She continues to drink black coffee alongside her high-fiber and scrambled egg breakfast.

The Science of MCT Oils

by Mireille Najjar

While medium chain triglyceride (MCT) oils are known to be effective fat substitutes for those with abnormal fat metabolism and absorption, it is unclear whether these fats are effective in increasing energy expenditure and assisting in significant weight loss.

What are MCTs?

Medium chain triglycerides are fats that are naturally found in coconut and palm kernel oil. They have an unusual chemical structure and are easily digestible. Unlike most fats that are broken down in the intestine and remade into a special form that can be transported in the blood, MCTs are absorbed intact and taken to the liver to be used for energy. They are broken down in a manner similar to that of carbohydrates.

One of the unique advantages of MCTs is that they provide about 10% fewer calories than large chain triglycerides (LCTs) – approximately 8.3 calories per gram for MCTs versus 9 calories per gram for LCTs. Additionally, shorter chain length means that MCTs are more quickly metabolized as fuel for immediate use by organs and muscles.

Another advantage of the energy-enhancing properties of MCTs is that, unlike LCTs, they do not require the presence of carnitine, a compound critical in energy production. This results in the production of ketones, which form as a result of fat metabolism. MCTs as a source of ketone bodies make these fats a suitable choice for those with increased energy needs, such as during post-surgery, normal or stunted growth, and for enhanced athletic performance.

Scientific Evidence for MCTs

MCT oils are useful fat substitutes, especially for people with AIDS who need calories but are unable to absorb or metabolize normal fats. For instance, a 1997 double-blind, placebo-controlled study in the Journal of the American Dietetic Association reported that MCTs can help improve AIDS-related fat malabsorption in 24 men and women with AIDS. Another double-blind study in Nutrition found similar results in 24 men with AIDS-related fat malabsorption. Some studies also suggest that MCTs might be helpful for those who have trouble digesting fatty foods because they lack the proper enzymes; however, a 1996 study in the Scandinavian Journal of Gastroenterology found that taking digestive enzymes seems to be more effective.

It has also been reported that MCTs may prevent fat storage. A 2008 paper published in the Asian Pacific Journal of Clinical Nutrition noted that MCTs, particularly when used as cooking oil, might decrease storage of excess calories as fat, since they are immediately burned for energy. Some studies have also found that MCTs might enhance body composition, or the ratio of fat to lean tissue.

The possibility of MCT oil as a valuable energy source during high-intensity physical exercise has also been studied. Since MCTs are more easily digested than other fats, they may quickly produce large amounts of energy after being consumed, which can enhance an athlete’s performance during intense physical activity. Not all scientific data supports this notion, though; the NYU Langone Medical Center reported insufficient evidence to link the effects of MCTs on increased energy expenditure amongst athletes.

MCTs and Weight Loss

Although MCTs have been proposed as a weight loss aid due to their quick digestibility and large energy provision, there have been mixed results linking MCTs and weight loss. According to the NYU Langone Medical Center, studies have generally not supported the use of MCTs for weight loss. Other studies, however, suggest that there is a potential link between MCT consumption and weight loss outcomes. For instance, in a 2008 study in the American Journal of Clinical Nutrition, researchers found that over the four months, overweight subjects that received MCT oil while on a weight-loss plan lost more weight (around four pounds) than those who consumed olive oil and concluded that MCT oil can be useful to enhance weight loss. It is uncertain, though, whether these MCT users would have continued to lose more weight had they continued to consume the oil after the four-month study period. Other small studies that typically lasted one to four months also observed similar results—dieters who used small amounts of MCT oil lost more weight than dieters who used liquid vegetable oil.

In addition to weight loss, scientific studies have suggested that substituting MCTs for other fats in a healthy diet may help to suppress appetite and support healthy weight and body composition. For instance, in a 14-day 1996 study in the International Journal of Obesity and Related Metabolic Disorders, researchers noted that substituting an easily-metabolized fat, such as MCTs, for other fats such as LCTs, in high-fat diets can limit excess weight gain usually produced by energy-dense diets. MCT oil consumption could thus be advantageous for those who want to gain muscle mass and decrease body fat.

What Can We Conclude?

With all of the overlapping evidence, it is difficult to pinpoint the specific functions of MCT oil. While we may not yet know all the benefits of this unconventional fat, what we can extrapolate is that further research with more study subjects is needed to determine how beneficial MCT oil really is for weight loss and increased energy expenditure. It is also apparent that MCT oil can be particularly useful for those who are unable to metabolize and absorb conventional fats.

At this point, we can safely claim that MCT oil can be used as a dietary substitute for salad dressings, sauces, or cooking as a source of beneficial fatty acids.

Mireille Najjar is a first-year NUTCOM student who thoroughly enjoys learning more about the effects of ketosis on weight loss and epilepsy treatment.

How Does a Ketogenic Diet Affect YOU? Part 1 of a 3 part series

by Katie Mark

If you could tap into your approximately 40,000 calories of stored fat during endurance exercise instead of relying on your 2,000 calorie storage of carbohydrate fuel, would you do it?

LeBron James did it by switching to a ketogenic diet.

But for those of us who aren’t athletes, can the ketogenic diet positively impact our health?

The controversial ketogenic diet

A ketogenic diet is a diet high in fats and very low in carbohydrates (less than 50 grams of carbs per day) and causes the body to start burning fat instead of carbohydrates by breaking down fat into molecules called ketones. As we saw in last month’s article, “The Basics of the Ketogenic Diet,” the diet was developed to help treat seizures in children who suffered from epilepsy.

Believe it or not, the brain, usually dependent on glucose from food, can also run using ketones. When you transition to a ketogenic diet, there is a period of time in which your body adapts to the change. Under normal circumstances, skeletal muscle will burn ketones for energy, but as “keto-adaptation” occurs, the muscles switch to burning fatty acids instead. This increases blood ketone levels and allows more ketones to supply energy to the brain. The change in energy sources makes keto-adaptation a gradual process taking at two weeks instead of a few days.

Today some nutritionists believe the ketogenic diet can be a valuable method for improving some health “biomarkers,” or signs of health your body creates. By examining these biomarkers, effects of the ketogenic diet can be measured.

In this part one of the three-part series on “How Does a Ketogenic Diet Affect YOU” we will look at what ketosis does for fasting glucose and insulin.

The ketogenic diet does what to my fasting glucose and insulin?

When we eat food, the carbohydrates we eat are converted to glucose and transported throughout the body to give us energy. Fasting blood glucose (sugar) measures the amount of glucose one has in his blood after fasting for at least eight hours.

Normally after we eat, our blood glucose increases as carbohydrates are digested. Then, sensing glucose in the blood, the hormone insulin is released which allows glucose in blood to enter cells and be used as energy.

However, on a ketogenic diet, there is very little carbohydrate. In this case, what happens to fasting glucose and insulin?

One study, published in the journal Nutrition and Metabolism, reported that people on a very low-carbohydrate, high-fat, low-calorie diet experienced decreased insulin levels. This was significant, because another group, also eating low calorie, but consuming a high-carbohydrate, low-fat diet did not experience the same level of change. There was a third group of men who ate a low calorie diet that was high in carbohydrate and high in unsaturated fats. All three groups ate low-calorie diets for eight weeks, then increased their calories to maintain their weight for another four weeks.

All groups experienced a decrease of 2% in fasting glucose with weight loss, independent of diet. Yet, those eating the very low-carb diet experienced a 33% decrease in fasting insulin concentration. This high-unsaturated fat diet had a decrease of only of 19% and the very low-fat diet experienced a 15% increase.

Post-meal insulin (as opposed to “fasted” insulin) was also lower in the low-carbohydrate diet group than in the other two groups. Researchers suggested that the high amount of fat may have delayed gastric emptying (when food leaves the stomach and enters the small intestine) of protein and weakened the release of insulin.

The study concluded that as long as there is weight loss, carbohydrate-restricted diets might be more effective than traditional weight loss diets in improving fasting and post-meal glucose concentrations and improving insulin sensitivity (which means how well body tissues “listen” to insulin and take in glucose from the blood).

Another study, published in the journal Experimental & Clinical Cardiology, examined the long-term effects of the ketogenic diet on weight loss and fasting blood glucose, as well as other various biomarkers, in 83 obese individuals. The ketogenic diet consisted of 20 – 30 g of carbohydrate (green vegetables and salad) and 80 – 100 g of protein (meat, fish, eggs, cheese, fowl and shellfish). Polyunsaturated and monounsaturated fats were also included. After 12 weeks, 20 g of carbohydrate were added for a total of 40 – 50 g of carbohydrate.

The subjects underwent fasting blood tests following eight, 16 and 24 weeks of treatment. Among other biomarkers looked at, the study found a significant decrease in the level of blood glucose, especially at week 24. The researchers concluded that using the ketogenic diet for a relatively long (24 weeks) period of time is safe. Yet, further studies need to examine the molecular basis of nutritional ketosis as this will help determine the potential therapeutic benefits from a ketogenic diet.

Now what?

As we see, a ketogenic diet may decrease both fasting glucose and insulin concentrations, with a potential increase in insulin sensitivity (how well our cells uptake glucose).

So why is this important to people? When carbohydrate consumption is restricted below a threshold in which it is not converted to fat, insulin sensitivity can often improve because less glucose is coming in. This is especially important for diabetic individuals because insulin resistance (the inability of muscle cells to take in glucose) is the main feature of type 2 diabetes.

Yet, diabetics are not the only ones who should monitor their fasting glucose and insulin. It’s important to control our blood sugars because type 2 diabetes develops over time when our body either doesn’t produce enough insulin or our body can’t use it properly. And if our body cannot use insulin, glucose remains in our blood at higher levels than normal, and this can cause many health complications.

How do you know what is a normal level? A normal level in fasting (of at least 12 hours) blood glucose test should be between 70 and 100 mg/dL. A level between 100 and 125 mg/dL is considered prediabetic and a level higher than 126 mg/dL signifies diabetes.

It’s important to keep in mind that every individual is different and may respond differently to the effects of this diet. Restricting carbohydrates can be very difficult. Therefore, focusing more on “good” carbohydrates, such as those with high fiber, may be a good option if you’re wondering what to do with this information, especially if you do not want to restrict carbohydrates. In the next part of this series, we’ll look at cortisol (the “stress hormone”) to see whether it goes up or down when the body adapts to nutritional ketosis.

Katie Mark is a first year Nutrition Communication student from Miami, Florida. She is a Cuban coffee connoisseur and has traveled to Cuba, where she hopes to live one day.


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