The Latest in Health & Medicine

child-appleHave you kept up-to-date on the research on nutrition, the human microbiome, and ancestral health lately? If not, here’s your chance to catch up. In these semi-regular posts I take a look at recently published articles, videos, and science that I find particularly interesting and that revolve around topics that are frequently discussed on this site, such as microbial exposure, physical activity, and ancestral diets. In today’s article I’ll primarily focus on nutrition, the human microbiome, and sleep. It’s now been a while since I last did one of these posts, so I’ve got lots of stuff to share that has been piling up.  Okay, let’s get to it…


Evolution and high protein diets

The evolutionary evidence indicates that so called “high protein diets” (20-30% total energy) and “very high protein diets” (30-40% total energy) actually represent the norm which conditioned the present day the human genome over more than 2 million years of evolutionary experience. The evolutionary template would predict that human health and well being will suffer when dietary intakes fall outside this range. Hence the current U.S. consumption of protein (15% total energy) may not optimally promote health and well being. There is now a large body of experimental evidence increasingly demonstrating that a higher intake of lean animal protein reduces the risk for cardiovascular disease, hypertension, dyslipidemia, obesity, insulin resistance, and osteoporosis while not impairing kidney function.

From the summary/conclusions of the 3-part series (Part 1, part 2, part 3) on evolution and high protein diets by Loren Cordain.

My comment: This is a great 3-part series on the evolutionary basis for the therapeutic effects of high protein diets. I’ve previously written several articles (e.g., here and here) that highlight the many benefits of eating more protein than what is typically recommended by public dietary guidelines and most nutritionists and dietitians.
As always, it’s important to keep in mind that the foods found at the grocery store today is very different from the foods our primal ancestors consumed. When it comes to animal products, the main focus should be on choosing grass-fed, organic, and/or wild foods whenever possible.

Want pizza, chocolate, French fries? Highly processed foods linked to addictive eating

Previous studies in animals conclude that highly processed foods, or foods with added fat or refined carbohydrates (like white flour and sugar), may be capable of triggering addictive-like eating behavior. Clinical studies in humans have observed that some individuals meet the criteria for substance dependence when the substance is food. Read more…

My comment: In my opinion, one of the biggest problems with contemporary Western diets is that they are loaded with foods that can elicit addiction-like responses. I’m not just talking about the obvious offenders like pizza and doughnuts, which have a nutrient composition that is very different from that of nutrient-dense, whole foods, but also dark chocolate, coffee, wheat, certain dairy products, and many other food items that a lot of people consume on a regular basis. A 30-day Paleo Diet challenge is a great first step for anyone who’s looking to overcome an addictive relationship to food, as it involves taking highly addictive foods out of the diet.

Pesticides in fruit and vegetables linked to semen quality

… men who ate the highest amount of fruit and vegetables with high levels of pesticide residue had a 49% lower sperm count and a 32% lower percentage of normally-formed sperm than men who consumed the least amount. Read more…

Diet swap has dramatic effects on colon cancer risk for Americans and Africans

… “Our study suggests that westernization of the diet induces changes in biomarkers of colon cancer risk in the colonic mucosa within two weeks. Perhaps even more importantly, a change in diet from a westernized composition to a ‘traditional African’ high fiber low fat diet reduced these biomarkers of cancer risk within two weeks, indicating that it is likely never too late to change your diet to change your risk of colon cancer.” Read more…

My comment: In my mind there is no doubt that the high prevalence of colon cancer in Western nations can largely be attributed to a low average intake of dietary fiber. Not only is the domesticated fruits and vegetables we consume in the industrialized world much lower in prebiotics than uncultivated varieties, but a lot of the carbohydrate-containing foods in the Western diet have been processed in such a way that the fiber content is dramatically reduced. To overcome the colon cancer epidemic we have to realise that we not only have to feed the human host, but also the trillions of microbes that reside in the large intestine.

Seven reasons to eat insects

  1. High in protein — A cricket is 65 percent protein whereas beef is about 50 percent.
  2. High in other nutrients — Insect protein contains a good range of amino acids and they also contain vitamins, minerals, unsaturated fatty acids and polyunsaturated fatty acids.
  3. Low in fat — Many insect species have less than 5 grams of fat per serving.
  4. Good for the environment — Insect farming can be a more sustainable practice because insects don’t need much space, can live under all sorts of conditions and easy to feed.
  5. Can be eaten a variety of ways — Insects can be pan-fried, boiled, sautéed, roasted, or baked with a bit of oil and salt. They can also be made into flour and used for bars, breads, crackers, and cookies.
  6. Abundant — Some parts of the world have over 300 species of insects. Something for everyone!
  7. Taste great — People describe the taste of insects as nutty with a similar flavor to shrimp and chicken. Grasshoppers, ant eggs, and wasps are considered a delicacy in several countries.
    Read more…

Caveman to Modern Homo Sapiens

Check out this great Paleo Diet infographic by Squatchy, Robb Wolf, and the people over at

Increasing dietary fiber reduces risk of developing diabetes

New research published in Diabetologia (the journal of the European Association for the Study of Diabetes) indicates that consuming greater quantities of dietary fiber reduces the risk of developing type 2 diabetes. Read more…

The chemical warfare on your plate

Most people don’t want pesticides sprayed on their foods, but they can’t avoid the natural pesticides found in the fruit and veggies they eat. Surprisingly, however, those endogenous plant toxins are not necessarily harmful. At normal doses many are harmless, and frequently beneficial – for example the sulphur containing compounds in broccoli, kale and cabbage appear to have anti-cancer properties. At higher doses though, plant insecticides may threaten health – for example the cyanide in almonds, especially bitter almonds, which can sometimes exceed safe limits as happened in the USA in 2014 leading to bags of healthy sounding ‘organic raw almonds’ being removed from the shelves due to their high cyanide content.

So how can these plant-made insecticides ever be good for us? Read more…

Fermented foods – Everything you need to know

My comment: I’ve talked a lot about the health benefits of eating fermented vegetables, kefir, and other fermented foods on this blog. In the video above from, Dr. Alan Logan, a leading expert on ancestral health, fermented foods, and the gut-microbiome-brain axis, explains what goes on during the fermentation of food and highlights some of the reasons why you should consider adding more fermented foods to your diet.


Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness

In the past 50 y, there has been a decline in average sleep duration and quality, with adverse consequences on general health. A representative survey of 1,508 American adults recently revealed that 90% of Americans used some type of electronics at least a few nights per week within 1 h before bedtime. Mounting evidence from countries around the world shows the negative impact of such technology use on sleep. This negative impact on sleep may be due to the short-wavelength–enriched light emitted by these electronic devices, given that artificial-light exposure has been shown experimentally to produce alerting effects, suppress melatonin, and phase-shift the biological clock. Read more…

My comment: In a recent article here on the blog I talked about some of the strategies I used to manufacture a good night’s sleep. My experience is well-aligned with what the research in this area tells us about optimizing sleep, in the sense that one of the things I’ve found to be particularly important is to not use my phone or computer right before bed.

This is what happens to your brain and body when you check your smartphone before bed

My comment: In the video above, Dr. Dan Siegel, clinical professor of psychiatry at the UCLA School of Medicine, lays out why bedtime screen viewing has such a negative impact on sleep. Well worth a watch, particularly for those who are still unconvinced that they should stop using their phone late at night.

The less you sleep, the more you eat

Factors influencing food intake have, and continue to be, a hotly contested subject. A new paper published in the SAGE journal, Journal of Health Psychology (JHP), suggests that disrupted sleep could be one factor contributing to excessive food intake and thus leading to long term chronic health damage in both adults and children. Read more…

My comment: These findings shouldn’t come as a surprise to those who’ve been following the research in this area. Getting more high-quality sleep should be high on the to-do list for anyone who’s interested in good health – and in particular those who have trouble losing weight and/or sticking with a healthy diet.

The Human Microbiome

Medicine’s next frontier: The microbiome

Sue Dillon, J&J’s global therapeutic head for immunology, listed conditions from autoimmune diseases including plaque psoriasis and rheumatoid arthritis, to inflammatory bowel diseases like Crohn’s and ulcerative colitis, asthma, diabetes and even cancer as potential targets for microbiome therapeutics. Read more…

My comment: Most of the probiotic supplement on the market today aren’t particularly effective. However, the research in this area is blooming, and many new supplements and microbiome modulators are in the pipeline. While I think it’s a mistake to think that these new products are going to solve all our problems, I definitely think there’s a lot of potential in this area.

Life in a World without Microbes

Microbes sustain life on this planet because of their myriad associations and biogeochemical processes. Nonetheless, their roles are not necessarily irreproducible. When you next hear someone claim that we cannot live without microorganisms, it would be appropriate to ask them to qualify the statement. Would we still be able to eat and digest food? Yes. Would life be extinguished in the absence of Bacteria and Archaea or in a world without any microbes? Not immediately, not all life, and potentially not for a long time.

In short, we argue that humans could get by without microbes just fine, for a few days.* Although the quality of life on this planet would become incomprehensibly bad, life as an entity would endure.

* If we do include mitochondria and chloroplasts as Bacteria, as we should, then the impact would be immediate—most eukaryotes would be dead in a minute. Read more…

‘Cure for obesity’ may not be for the squeamish: Scientists hunt for ‘clean’ gut bacteria in faeces extracted from mummies

The key to a ‘cure’ for obesity might lurk in an unlikely place – in the bowels of mummified corpses from 3,000 years ago.

Scientists believe that one of the causes of today’s obesity academic may be antibiotics, which have changed humanity’s ‘gut flora’, the bacteria that live inside us.

Researchers believe that a possible ‘cure’ for obesity might be to repopulate our guts with ancient bacteria from a time before antibiotics existed. Read more…

Among Trillions of Microbes in the Gut, a Few Are Special

Independent researchers around the world have identified a select group of microbes that seem important for gut health and a balanced immune system. They belong to several clustered branches of the clostridial group. Dubbed “clostridial clusters,” these microbes are distantly related to Clostridium difficile, a scourge of hospitals and an all too frequent cause of death by diarrhea. But where C. difficile prompts endless inflammation, bleeding and potentially catastrophic loss of fluids, the clostridial clusters do just the opposite—they keep the gut barrier tight and healthy, and they soothe the immune system. Read more…

Special microbes make anti-obesity molecule in the gut

Microbes may just be the next diet craze. Researchers have programmed bacteria to generate a molecule that, through normal metabolism, becomes a hunger-suppressing lipid. Mice that drank water laced with the programmed bacteria ate less, had lower body fat and staved off diabetes — even when fed a high-fat diet — offering a potential weight-loss strategy for humans. Read more…

Here’s What Eating Nothing But McDonalds for 10 Days Does to Your Gut Bacteria

Eating McDonald’s for 10 days straight can wreak havoc on the healthy bacteria in your body that makes up your microbiome, according to one man who tried it so the rest of us don’t have to.

Tim Spector, professor of genetic epidemiology at King’s College London, enlisted his son Tom, a genetics student at the University of Aberystwyth, to undergo an experiment where he subsisted on McDonalds food for ten days. Tom could eat a Big Mac or Chicken nuggets as well as fries and Coke — and Dad footed the bill.

… The results revealed that Tom’s gut microbes were “devastated,” Spector reports in the The Conversation. Tom had lost around 40% of his bacteria species, about 1,400 types. That loss of microbiome diversity is of concern since that can be a red flag for health issues such as obesity and diabetes. Read more…

The guts of the issue

… the bacteria in the intestinal system must be viewed as an ecosystem. Everything is connected with everything else, and this diversity must be there in order for us to stay healthy. You can’t just remove some “evil” bacteria, as one does with antibiotics, and believe that this is purely beneficial. Neither can you gobble up “nice” bacteria in the form of so-called probiotics, for example some types of yoghurt, and believe that this is purely beneficial as well. Read more…

My comment: This is a really great piece on the microbiome. Dr. Tore Midtvedt, one of the researchers who is interviewed for the article, is one of my favorite scientists. A really smart guy that has a lot of wisdom to share. Well worth a read.

Widely used food additives promotes colitis, obesity and metabolic syndrome, shows study of emulsifiers

Emulsifiers, which are added to most processed foods to aid texture and extend shelf life, can alter the gut microbiota composition and localization to induce intestinal inflammation that promotes the development of inflammatory bowel disease and metabolic syndrome, new research shows. Read more…

The Microbes on the Handprint of an 8-Year-Old After Playing Outside

We all know our bodies are home to countless millions of bacteria and microorganisms, but without seeing them with our bare eyes it’s almost impossible to comprehend. This petri dish handprint created by Tasha Sturm of Cabrillo College, vividly illustrates the variety of bacteria found on her 8-year-old son’s hand after playing outdoors. The print itself represents several days of growth as different yeasts, fungi, and bacteria are allowed to incubate. Read more…

Toddler temperament could be influenced by different types of gut bacteria

The microbiome of a toddler’s gut may influence their behavior, a new study suggests. Scientists found correlations between temperament and the presence of specific types of intestinal bacteria in both girls and boys. Read more…

For Healthier Skin, Check Your Gut, Not Your Bathroom Cabinet

While one chocolate bar, a couple of drinks, or a few evenings of fried food won’t permanently alter your health, you’ll probably “feel” those diet decisions immediately, and it’s not going to be comfortable: You might bloat up, get a headache, or experience a disconcerting dip in energy. Keep up the unhealthy eating and drinking for more than a few weeks, and your skin will likely start to reflect your behavior in the form of breakouts, blotchiness, dryness, or unhealthy pallor.

That’s because your skin—all 21 square feet of it—isn’t just the largest organ in your body. It’s also the canary in the coalmine for your digestive health. Skin conditions like acne, rosacea, and eczema are often a sign that something serious is going on deep within your gut. Read more…

My comment: While this article misses the mark on a couple of points, the main message is correct: The first step towards healthier skin is to repair the gut. As I’ve repeatedly said here on the blog, I believe gut dysbiosis and leaky gut are the main causes of acne vulgaris and many other skin disorders that are highly prevalent in the Western world. My tip for those who suffer from acne: Throw out the benzoyl peroxide and focus on repairing the gut and cooling down inflammation.

Dr. Justin Sonnenburg: Gut inflammatory trajectories and treatment of chronic disease

My comment: Dr Justin Sonnenburg, author of the new book called “The Good Gut”, is a leading researcher in the microbiome field. In the video above he discusses how bacteria can create a pro-inflammatory or anti-inflammatory environment locally in the gut, and how these inflammatory trajectories give us insights about how to treat chronic disease. Well worth a watch.

Mothers can pass traits to offspring through bacteria’s DNA, mouse study shows

A new study in mice has shown that the DNA of bacteria that live in the body can pass a trait to offspring in a way similar to the parents’ own DNA. According to the authors, the discovery means scientists need to consider a significant new factor — the DNA of microbes passed from mother to child — in their efforts to understand how genes influence illness and health. Read more…

My comment: The microbial genomes you receive from your parents during birth, breastfeeding, and other forms of contact are in some respects even more important than the human genes you inherit; particularly when it comes to the susceptibility of developing chronic illnesses associated with poor immunoregulation and chronic low-grade inflammation. In other words, taking good care of the microbiome is particularly important if you’re planning on having children.

Other topics

Lean despite many calories

Scientists have identified an enzyme in mice that is involved in obesity and metabolic disruptions associated with it, such as type 2 diabetes. When the investigators turned off the enzyme in experiments, the animals did not gain any weight despite being fed a diet that was rich in fat and caloric content. Furthermore, they did not develop diabetes. So far, however, there is still not much evidence that this mechanism also plays a role in humans. Read more…

The myopia boom

East Asia has been gripped by an unprecedented rise in myopia, also known as short-sightedness. Sixty years ago, 10–20% of the Chinese population was short-sighted. Today, up to 90% of teenagers and young adults are. In Seoul, a whopping 96.5% of 19-year-old men are short-sighted.

Other parts of the world have also seen a dramatic increase in the condition, which now affects around half of young adults in the United States and Europe — double the prevalence of half a century ago. By some estimates, one-third of the world’s population — 2.5 billion people — could be affected by short-sightedness by the end of this decade. “We are going down the path of having a myopia epidemic,” says Padmaja Sankaridurg, head of the myopia programme at the Brien Holden Vision Institute in Sydney, Australia.

This threat has prompted a rise in research to try to understand the causes of the disorder — and scientists are beginning to find answers. They are challenging old ideas that myopia is the domain of the bookish child and are instead coalescing around a new notion: that spending too long indoors is placing children at risk. “We’re really trying to give this message now that children need to spend more time outside,” says Kathryn Rose, head of orthoptics at the University of Technology, Sydney. Read more…

My comment: Myopia is an evolutionary mismatch condition. Hopefully soon more research focus will be directed towards possible strategies that can be used to prevent and possibly reverse short-sightedness.

Have you come across some interesting new research or articles that you would like me to comment on? If yes, share them in the comment section below.


Picture: Creative Commons picture by Sharon & Nikki McCutcheon. Some rights reserved.


  1. Jennifer says:

    Wow; what a detailed article. Great information. A little grossed out by the fecal transplant and eating insects but I’ll live 🙂

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