A diet of berries, roots, nuts and the occasional hapless creature. Would you try it and would it make your life better? asks Durban-based dietitian Keri Strachan.
Should we revert to the hunter-gatherer ‘Caveman’ diets of our ancient ancestors? Will it curtail the modern epidemics of obesity, hypertension, diabetes and heart disease? Considering how our modern day diet has changed in the last 10,000 years this may seem a good idea. But how practical will this diet be?
It is regularly suggested that we should be reverting to our hunter-gatherer diets of our ancient ancestors in order to curtail the ongoing epidemics of obesity, hypertension, diabetes and heart disease. If we consider briefly how our modern day diet has changed in the last 10,000 years one may be enthusiastic to take this stance, particularly when we make our resolutions for better nutrition.
A hunter-gatherer or Paleolithic diet typically consists of wild animal food sources (such as meat, bone, marrow and organs) and uncultivated plant sources (such as fruit, vegetables, nuts), excluding all grains, dairy and legumes.
To put this into perspective, our ancestors who ate this way are believed to have existed from two million years ago until 10,000 years ago, when they began cultivating plants and domesticating animals.
The benefits of this wild unprocessed diet are of course the greater level of activity required to forage and gather food supplies as well as the leaner meats sources from the wild animals, and the rich sources of polyunsaturated and monounsaturated fats, fibre, vitamins, minerals, antioxidants and other phytochemicals from the high intake of plant food sources. But importantly hunter-gatherers were not free to determine their diet, rather it was predetermined by their environment, for example they would not have eaten meat every day.
Modern day humans now consume a large amount of refined (low fibre, high calorie-density, high sugar) cereal products, dairy products, and legumes, with very little fruit and vegetables. Many meat sources are highly processed usually containing higher levels of saturated fat and salt, thus giving more salt and saturated fat per portion of meat. And on top of this, meat is eaten everyday in excessive amounts.
It is argued that these contemporary eating habits have lead to the development of the lifestyle diseases that we now contend with i.e. heart disease, metabolic syndrome, diabetes, hypertension, osteoporosis. If it took literally millions of years for our ancestors to adapt their core metabolism and physiology due to evolutionary forces for their Paleolithic diet, then could our contemporary diet, of only 10,000 years have had the same ability to adapt our bodies to cope with this nutrition? Clearly not. Studies have demonstrated that current day humans given a Paleolithic diet experience improvements in blood pressure, glucose tolerance, reduced insulin secretion, increased insulin sensitivity, and reduced triglyceride and LDL cholesterol levels. Obvious reasons for this health benefit include that most wild foods are bulky low energy foods in terms of their volume and as a result of the relatively slow human digestive tract would naturally control appetites to prevent obesity and consequently the related diseases.
The supply of meat would be opportunistic, with the main limitation to frequency being the high energy cost of acquisition, so although it would be eaten at times in large amounts, the basis of the diet would be plant food sources. Such animal sources of food would be comparatively energy-dense and would be mostly useful for their contribution to fat stores for use as energy during times of low food availability. Hunter-gatherers typically spent a large proportion of their day active foraging and hunting for food and thus their activity levels are very high, which would directly contribute to these health benefits.
Rather than trying to revert completely to a Paleolithic diet which would be difficult to sustain and almost impossible for athletes to achieve their high calorie demands, we need to remember our long evolutionary heritage and heed current recommendations to increase the number and variety of fresh fruit and vegetables (and the antioxidants will protect us from these lifestyle diseases), decrease intakes of processed meat products, choosing plain meat, chicken and fish products.
Incorporate healthy plant and nut fats, and rather choose low fat animal and dairy products.
Limit our intake of highly processed and fast foods (biscuits, cakes, breads), due to their energy-density, high salt and, in some cases, low nutrient density (sugary cereals, sugary drinks).
For our valuable carbohydrate requirements choose more whole grains such as barley, bulgur wheat, brown rice, whole wheat pasta, seeded high fibre breads, beans and legumes.
This will surely prevent the consumption of excessive calories and allow better weight management and in the long term hopefully curtail the health epidemic we are a part of.