Evolutionary history and nutrition – how personal does it get?

Eating healthy food is not as clear cut as you might think. When it comes to diet, what is ‘healthy’ and ‘unhealthy’ is highly dependent on the individual. The role of cultural adaptation can strongly influence genotype amongst individual groups of people on a micro-evolutionary scale. We need to consider how these changes affect the way individuals respond to certain kinds of food and the types of variation in responses amongst distinct populations.

The Weizmann Institute in Israel’s Personalised Nutrition Project investigated the variation in responses to a range of different food types from individual to individual. Each participant’s microbiome (the balance of micro-organisms or bacteria that live on and in your body) was analysed using stool samples to see what types of bacteria were present. The profiles and blood glucose responses of those studied varied wildly.

The preliminary results from the study involving 800 people revealed the there was incredibly high variability in how different people responded to the same foods. The study measured an individual’s blood glucose responses to both ‘healthy’ and ‘unhealthy’ foods. Surprisingly, while some people responded with spikes in blood glucose to supposedly high glycemic index foods, others did not produce any such spikes. The researchers then used an algorithm to produce tailored diets for individuals. Some conventionally unhealthy foods were fine for certain people to eat, and typically healthy foods were considered unsuitable for others.

The study did not take the participants’ ancestry into account. However, microbiome research is very much an emerging field within the spheres of archaeology and anthropology and has given some promising results with regards to variation between individual cultural groups. The University of Oklahoma’s Laboratories of Molecular Anthropology and Microbiome Research has produced some intriguing research working with ancient coprolite (excrement) samples and modern-hunter gatherer DNA.

Their research has revealed that the hunter-gatherer populations, whilst geographically isolated from each other, were much more similar in microbiome content than more agriculturalist populations adjacent to them. The microbe ‘Treponema sp.‘ which is associated with the digestion of fibrous plant materials is present in populations living a traditional lifestyle but absent in all of those living in industrialised societies. The microbe is also present in modern-day ape guts and in ancient coprolite samples. The lifestyle of modern humans has had a great impact on the way our microbiome is structured.

This invariably presents some massive implications for human health and disease. Autoimmune diseases such as multiple sclerosis, diabetes, and eczema are greatly influenced by our individual microbiomes. An understanding of what is beneficial and what is harmful to us through molecular anthropology and microbiota profiling would potentially solve some of the world’s biggest health problems. Running individual profiling as per the Weizmann Institute is likely to be too expensive for many people.

Therefore, the archaeological research discussed above is paramount in being able to provide widened accessed to understanding what might or might not be good for individual ethnic groups. This research could idealistically be used for production of guidelines for good and bad food groups for individual ethnic groups. The information could be distributed in a public health setting and stimulate a paradigm shift in the arena of the conventional recommended diet model.

References

Obregon-Tito, A., Tito, R., Metcalf, J., Sankaranarayanan, K., Clemente, J., Ursell, L., Zech Xu, Z., Van Treuren, W., Knight, R., Gaffney, P., Spicer, P., Lawson, P., Marin-Reyes, L., Trujillo-Villarroel, O., Foster, M., Guija-Poma, E., Troncoso-Corzo, L., Warinner, C., Ozga, A. and Lewis, C. (2015). Subsistence strategies in traditional societies distinguish gut microbiomes. Nature Communications, 6, p.6505.

Is milk Paleo? For 35% of us, yes.

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Photo Credit: Kabsik Park

Is there is one single diet that the entire human species should follow? Probably not. Perhaps the picture is much more complex than what the Paleo diet postulates? Several archaeological studies have revealed that biological differences between human populations can arise as a result of repeated cultural activities. Cultural practices present as a type of ‘selection pressure’ on the human body and can result in physiological and morphological change within a population’s genotype. If we are to consider just how diverse the human species is culturally, the range in scope of human societal and behavioural adaptations (human niche construction) to environmental challenges is as variable as the planet’s geographies. This range in geographies and environments affects resource accessibility and, in turn, each culture’s resultant mechanism of coping with unique societal challenges. Consider the case of the lactase persistence gene in dairying versus non-dairying populations. Studies suggest that around 65% of the world’s population is unable to tolerate lactose into adulthood.

The ability to digest lactose sugar found in milk disappears in humans later in life as it is no longer a necessity past breastfeeding. However, following the advent of dairying and pastoralism, the ability to digest milk and lactose continued into adulthood with the expression of the Lactase Persistence (LP) gene. Genome biologist Ed Green discusses this in the video below.

The Lactase Persistence in the early Cultural History of Europe research project has investigated the prevalence of Lactase Persistence gene within European populations and the archaeological evidence surrounding the adoption of the genetic allele for its expression within these populations. Zooarchaeological and fat residue evidence from the Neolithic in Europe has provided supplementary evidence to support that the widespread presence of the gene within European populations has arisen as a result of the commonly adopted cultural practice of dairying that occurred on the continent historically.

Studies using modern populations have shown that in some areas of the world, such as southern Africa and eastern Asia, have populations where under 10% of adults are able to digest milk properly. Areas of the world with the highest number of people who can drink milk in adulthood are most of Northern Europe (around 90% in Swedish and Danish populations) and Southern Europe and the Middle East (approximately 50% in Spanish, French and pastoralist Arab populations).

This variability in lactase persistence is intrinsically linked to the cultural practices of individual ethnic and social groups, especially in the case of non-dairying versus dairying groups across Africa. So, are milk and dairy products Paleo or not? The evidence renders this debate redundant as the ability to digest such products is tightly linked to one’s own unique genetic ancestry and evolution as a result of cultural heritage.

References

Curry, A., 2013. Archaeology: The milk revolution. Nature.

Leonardi, M., Gerbault, P., Thomas, M.G., Burger, J. 2011. The evolution of lactase persistence in Europe. A synthesis of archaeological and genetic evidence. International Dairy Journal.

Ranciaro, A., Campbell, M.C., Hirbo, J.B., Ko, W.Y., Froment, A., Anagnostou, P., Kotze, M.J., Ibrahim, M., Nyambo, T., Omar, S.A., Tishkoff,

S.A. 2014. Genetic Origins of Lactase Persistence and the Spread of Pastoralism in Africa. American Journal of Human Genetics.

Tishkoff, S.A., Reed, F.A., Ranciaro, A., Voight, B.F., Babbitt, C.C., Silverman, J.S., Powell, K., Mortensen, H.M., Hirbo., J.B., Osman, M.,

Ibrahim, M., Omar, S.A., Lema, G., Nyambo, T.B., Ghori, J., Bumpstead, S., Pritchard, J.K., Wray, G., Deloukas, P. 2007. Convergent adaptation of human lactase persistence in Africa and Europe. Nature Genetics.

Winter Warmers: never underestimate the power of a hot tomato soup

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Brrr it’s chilly! I’m glancing glumly at my iPhone’s weather app – yep, a bleak 4 degrees blinks across the screen, but have no fear fellow Londoners, the handy cost-effective can of Heinz Tomato Soup packs more of a nutritional punch than we first thought!

5 Tomato-tastic Facts that will blow your noggin!

1) Breathe a sigh of relief: Tomatoes can actually help reverse damage caused by smoking!  Chlorogenic and coumaric acid, the two main ingredients in tomato soup, eliminate carcinogens!

2) Help for the diabetic: Tomatoes contain high levels of the element ‘chromium’ to help aid in blood glucose regulation which is important for all of us!

3) No bone to pick: Tomatoes are in abundance of vitamins C and K which are vital for bone health

4) Hearty food: Tomatoes are also rich in vitamin B and potassium: two key ingredients for lowering blood pressure

5) Cancer Fighter: Tomatoes are high in carotenoids (a type of antioxidant molecule) that protect the body from free radical damage

Why Kale is your new best friend

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with thanks to greg.turner via CreativeCommons

This crispy, curly vegetable packs a lot more punch than first meets the eye, not only delicious as crunchy chips but also steamed!

1) It is low calorie and has zero fat but high in fibre meaning you’ll be fuller for longer! It is also packed full of nutrients, vitamins, folate and magnesium

2) It’s higher in iron than BEEF which is essential for good haemoglobin levels and in preventing anaemia for better transport of oxygen in the body

3) It’s packed with vitamin K which can not only protect against various types of cancers but has also been proven to help those suffering from Alzheimer’s disease

4) It’s a prime detox food that is high in fiber and sulphur which are good for keeping your liver healthy

5) It’s high in calcium which is great for preventing osteoporosis and bone health

Sources: MindBodyGreen