I have often spoken about our instinctive taste drives but recently, while looking for a reference on this topic, I realized that I had not written about it.
It appears that we have at least 4 biological taste drives that regulated how we survived in ancient times without food pyramids or dietitians. These drives are determined by our subconscious minds and I discovered an interesting statistic that our conscious mind engages around 2000 synapses while our subconscious mind utilizes over 4 million synaptic pathways. Clearly we are way more subconscious than logical.
So what are these taste drives and how do they affect our nutrition today?
1. We clearly have an instinctive taste drive for sweetness even if the taste is hidden in sauces, piquant dressings and other savoury things.
2. Then there’s a carbohydrate craving for more starchy foods or complex carbs which impart a sense of fullness and satiety.
3. It's easy to see that we are driven to fat in foods and the combination of fat and sweet is almost culturally ubiquitous.
4. And lastly is our fourth drive which is for those essential phytonutrients that we absolutely need for on-going good health – minerals, antioxidants, anti-inflammatories, cellular repair compounds, enzyme co-factors and so on. See this page for more on phytonutrients which are our evolutionary survival foods.
We appear to also have a predilection for Maillard products leading us to using fire in cooking our food and consequently improving the bioavailability of some nutrients. We had to learn to make fire before this drive became relevant but it did allow our brains to grow larger and more neurologically complex than was possible on a raw food diet alone.
I include my own experiences of living off the land with the many Aboriginal families and individuals with whom I have spent time in the Outback and around the coastline because relying on Australian wild foods exclusively as in the traditional Aboriginal diet really highlights the significance of these taste drives.
Meeting the need for sweetness from fruits, wild honey, honey ants, tree saps, lerp and other sources of sugars would generally mean lots of work and with fruits particularly, there would be fibre and those phytonutrients I listed above.
This leads me to a discussion of the nature of the sugars providing this sweetness: The sugar we use in cooking and as table sugar comes from three plants – sugar cane, sugarbeet and palm sugar. It goes under the scientific name of sucrose and is a disaccharide (two-sugar components) made up of a molecule of glucose and one of fructose. I have addressed the impact on our health of the rising sucrose intake in modern times here but the deleterious effects of a high sucrose intake are yet to be fully understood. We know sugar excess promotes ageing at a cellular level, obesity, diabetes, pancreatitis, macular degeneration, depressed sperm count and even accelerates loss of bone weight and mass and negatively affects mineral absorption. The full story may take decades yet to fully comprehend but in the meantime, it may be helpful to define fructose as a bad sugar simply because we have outstripped the evolutionary advantage of being able to find fructose-rich foods and benefit from the fat storage it promotes and the uric acid that results as we metabolize it. Read more about the good and bad sugars here.
However, our foragers’ sweetness drive would also provide trehalose (a unique di-glucose molecule similar to maltose but with more intricate and functional bonding), fructose and glucose as the predominant sugars along with a host of functional (good) sugars which aid absorption of nutrients into our cells. Good sugars also appear to assist in the expulsion of toxins from our cells by fueling an active cellular pump recently described.
Other nutrients that sweetness-driven foragers would be getting include plenty of fibre (both soluble and insoluble) from the sweet fruits; a nutritional cocktail from wild honey (pollen is an extremely rich food of simple amino acids, waxes and good sugars) and a range of both water and fat soluble antioxidants. This last point is interesting because modern fruits typically lack the fat-soluble vitamins found in wild foods in the same way as offal from domesticated animals is devoid of vitamin C unlike game animal offal which can be a rich source of this antioxidant. Aboriginal Elders often had a reduced dietary range with their increasing years but were given the liver and other offal from the hunts as acknowledgment of their social status. This may have been their dominant source of vitamin C as foraging for fruits declined with age.
This craving is more for complex carbohydrates such as starches today. However, with wild foods, fructans or oligofructose (cross-linked chains of fructose) such as inulin were more common than simple glucose starches in that have been bred into modern vegetables.
Inulin is metabolized by fermentation in the lower intestine by bifido-bacteria which also reduce populations of putrefactive and pathogenic bacteria. Additionally, colonic fermentation does not add fructose or other sugars to the blood so they do not have an insulin response or other deleterious, pre-diabetic effects.
Bifido-bacteria are highly beneficial to our health. They significantly increase the absorption of key minerals in the diet eg, calcium, magnesium, iron, copper and zinc and these minerals are deficient or out of balance in our modern diets. The growth and abundance of good gut bugs such as bifido-bacteria reduces the levels of undigested, anti-nutritional dietary carbohydrates; increases our resistance to pathogens, reduces blood fats and the risk of coronary heart disease, provides anti-tumor effects, stimulates immunity and has been shown to be anti-cancer.
A craving for healthy oligofructose foods would lead hunter-gatherers to underground storage organs of many kinds; yams, tubers, fleshy roots and other carbohydrate stores as well as the carbohydrate reserves at the base of some plant leaves and in a range of edible seeds (grasses and shrubs). In other parts of the world, this drive has led human populations to become reliant on wheat, rice, corn, potatoes, barley, millet, cassava, yams and/or sweet potato as dietary staples. However, even where these carbohydrates were consumed traditionally, hunter-gatherers would have eaten them as seasonal, occasional foods, rich in fibre and particularly soluble fibre, They also lacked the simple starches bred into modern varieties or the sucrose loads in other modern foods eg sweet corn, sweet peas, sweet potato. Unfortunately, reducing dietary variety and adopting a small range of foods as staples, living sedentary lifestyles and replacing phytonutrient-rich fruits and vegetables with these ‘rubbish’ carbohydrate edibles had and continues to have far-reaching health ramifications.
Again, the wild food sources of the more satiating, complex fructans were infinitely more appropriate for our on-going good health than the agricultured substitutes on which we depend for a large part of our energy intake today. Today we almost begin to salivate just at the thought of a pasta, rice or potato dish and we even often plan our meals around the carbohydrate component.
Meeting our drive for fat would provide proteins whether from hunted animals and seafood or from tree nuts. Again, plenty of antioxidants (game animal offal even contains vitamin C) and lots of good fats as saturated fats are rare in the wild. Satisfying the drive for fat (and the above drives too) would entail very short bursts of very strenuous exercise or some endurance energy expenditure digging for burrowing animals and yield other resources for a hunter-gatherer lifestyle (skins, bones for spear tips and knives, sinews for tools) and a deepening relationship with Country as the land was managed with fire and water channeling for maximum food supply.
The Drive for Phytonutrients
These include antioxidants, anti-inflammatories, anti-allergens, anti-rogue cell (antiproliferatives, pro-apopotics, anticarcinogens, antimutagens), immune boosters and cytokine controllers, adaptogens (normalizers), organic acids, organ and cellular protectants (brain, heart, liver, kidney, pancreas, lungs, blood vessels, lymphatics, skin, reproductive organs and the all important, intra-cellular organelles - our mitochondria), live enzymes and enzyme regulators, vitamin activators, good sugars (any sugars except sucrose and fructose), soluble and insoluble fibre and bioavailable minerals. In other words, all the biochemical tools in our cellular maintenance toolbox.
Phytonutrients are only just beginning to be understood more fully and as yet, we have few recommended daily allowances for the bulk of them. Some are even the basis of whole new strands of medicine and health research for example, metaflammation, glycobiology, epigenetics, nutrigenetics and nutrigenomics. Lifestyle medicine attempts to reflect good health strategies encompassing these areas collectively and much of the research in this area reflects the traditional Aboriginal diet as being closer to the ideal for humans. Perhaps 60,000 years of human trials and practical adaptations to the environment are useful tools for the study of modern nutrition.
If we don’t get our taste drives met then current thought is that we unconsciously keep eating until we do. The drives for sweet and fat are easily met with today’s foods. Sucrose, with its content of 50% fructose as a bad sugar, is in nearly every processed food and continues to be bred into fresh produce for sweetness. We know it makes food more addictive and is mostly combined with fat for added appeal. However, the need for phytonutrients subconsciously motivates us to eat more food. What results is that we over-indulge in bad sugars and fat (bad energy perhaps) as we hunt those phytonutrients which are either at low concentrations in modern foods or completely absent. Obesity and all its complications and all the other diseases of nutrition, including cancer, are the end game.
The fruit that we eat today has been altered (by humans) for various traits, especially large size and high sugar content. In the industrial age, selection sped up and favored longer shelf life and size/shape uniformity over flavor. Prior to human manipulation, the fruits were far smaller, less sweet, and not very abundant.
Too true Egi. Unfortunately with the ‘improvements’ we bred in there was a cost. This was the fall in the healthy levels of fibre, micro-sugars, antioxidants and many other micro-nutrients so what we have as fresh produce today is a shadow of the food quality with which we evolved.