Nutrition and Health

This is an essay highlighting the fundamental importance of agriculture (historical and present) in the agro-socioeconomic evolution of human societies, from the times of the hunter/gatherers to the modern day. Attention is drawn in the text to the importance of deforestation in relation to micro and macro climate changes, and the vital role of carbon dioxide to plant and animal life. The essay also relates the world’s natural resources to the present unsustainable population pressures.

Life originated on this planet about 3 billion years ago. For the first 2.5 billion years of life there was ample opportunity for DNA modification. Yet there is no evidence of significant change in life forms during that time. It was not until about 600 million years ago, when the oxygen tension rose to a point where air-breathing life forms became thermodynamically possible, that a major change can be abruptly seen in the fossil record. The sudden appearance of the 32 phyla in the Cambrian fossil record was also associated with the appearance of intracellular detail not seen in previous life forms. That detail was provided by cell membranes made with lipids (membrane fats) as structural essentials. Lipids thus played a major, as yet unrecognised, role as determinants in evolution. The compartmentalisation of intracellular, specialist functions as in the nucleus, mitochondria, reticulo-endothelial system and plasma membrane led to cellular specialisation and then speciation. Thus, not only oxygen but also the marine lipids were drivers in the Cambrian explosion. Docosahexaenoic acid (DHA) (all-cis-docosa-4,7,10,13,16,19-hexaenoic acid, C22:6ω3 or C22:6, n-3, DHA) is a major feature of marine lipids. It requires six oxygen atoms to insert its six double bonds, so it would not have been abundant before oxidative metabolism became plentiful. DHA provided the membrane backbone for the emergence of new photoreceptors that converted photons into electricity, laying the foundation for the evolution of other signalling systems, the nervous system and the brain. Hence, the ω3 DHA from the marine food web must have played a critical role in human evolution. There is also clear evidence from molecular biology that DHA is a determinant of neuronal migration, neurogenesis and the expression of several genes involved in brain growth and function. That same process was essential to the ultimate cerebral expansion in human evolution. There is now incontrovertible support of this hypothesis from fossil evidence of human evolution taking advantage of the marine food web. Lipids are still modifying the present evolutionary phase of our species; their signature is evident in the changing panorama of non-communicable diseases. The most worrying change in disease pattern is the sharp rise in brain disorders, which, in the European Union, has overtaken the cost of all other burdens of ill health at €386 billion for the 25 member states at 2004 prices. In 2007, the UK cost was estimated at £77 billion and confirmed in 2010 at £105 billion – greater than heart disease and cancer combined. The rise in mental ill health is now being globalised. The solution to the rising vascular disorders in the last century and now brain disorders in this century lies in a radical reappraisal of the food system, which last century was focussed on protein and calories, with little attention paid to the requirements of the brain – the very organ that was the determinant of human evolution. With the marine fish catch having plateaued 20 years ago and its sustainability now under threat, a critical aspect of this revision is the development of marine agriculture from estuarine, coastal and oceanic resources. Such action is likely to play a key role in future health and intelligence.

Older literature on infantile autism accompanied by mental retardation, focussed on epilepsy, cerebral palsy and microcephaly. Multiple adversity was needed to delay growth sufficiently to pruning of connection between Hippocampus and Singulum in its centre, SMA and inhibitory cells in Cerebellum in the synaptogenesis in infancy. Temporary macrocephaly was observed. Today, macrocephaly dominates the discussion. One single adversity, deficient “brain food”, seemingly retards growth sufficiently to cause excess pruning with absent activity in inhibitory Purkinje cells in Cerebellum, the SMA and A DEFICIENT, LACKING DELAYED RESPONSE FUNCTION. The brain needs time to adapt, but the Delayed Response Task is lost. Microcephaly predominates at puberty. We wanted to understand cerebellar reactions more fully.

We have determined and compared the concentration levels of retinol and β-carotene in the plasma of three Sudanese women groups (displaced southern Sudanese women (DSSW), non-displaced southern Sudanese (NDSSW) and northern Sudanese women (NSW)), who were either pregnant or non-pregnant; and in their neonates (cord plasma). Plasma samples were analysed by high-performance liquid chromatography using reversed-phase column and diode-array detectors. The results revealed that retinol and β-carotene in the plasma of non-pregnant and pregnant women in the three groups were very low compared with studies reported elsewhere. Over 50% of pregnant DSSW and NDSSW had a low concentration of retinol plasma (< 0.70 µmol/L), and about 15–20% were deficient (< 0.35 µmol/L) according to World Health Organization criteria. Although the average retinol concentration in the plasma of pregnant NSW was > 0.70 µmol/L, which suggests sufficiency status, 32% showed lower levels and 10% were deficient. Plasma retinol β-carotene levels in the neonates’ cords were also lower than their mothers and in comparison with other studies. These findings are in agreement with previous survey data and clinical reports, which also suggest that vitamin A deficiency is of great concern in the country. We concluded that insufficient intake of food of animal origin and repeated malarial and other parasitic diseases are the most likely causes of vitamin A deficiency.

Diet and lifestyle have an impact on the burden of ill health and non-communicable ailments such as cardiovascular disease (including hypertension), obesity, diabetes, cancer and certain mental illnesses. The consequences of malnutrition and critical unbalances in the diet with regard to sugar, salt and fat are becoming increasingly manifest in the Western world and are also gradually influencing the general health condition for populations in developing countries. In this topical mini-review I highlight the lack of deliciousness and umami (savoury) flavour in prepared meals as a possible reason for poor nutritional management and excess intake of salt, fat and sugar. I argue that a better informed use of the current scientific understanding of umami and its dependence of the synergetic relationship between monosodium glutamate and certain 5′-ribonucleotides and their action on the umami taste receptors will not only provide better-tasting and more flavoursome meals but may also help to regulate food intake, in relation to both overeating and nutritional management of elderly and sick individuals.

Following his last edition of the Origin of Species in 1872, Darwin spent much of the rest of his life searching for possible mechanisms, such as the pangenes in the blood, which would communicate information from the environment to the genome. In each of his six editions of the ‘Origin’, he stated that there were two forces in evolution – natural selection and conditions of existence. Of the two, he claims that the latter is the more powerful. In so doing, he recognized that natural selection could only operate within the bounds of possibility, that is the environment. August Weismann claimed that conditions of existence had no place in evolution. His publication, the ‘All-sufficiency of natural selection’, was based on mutilation (cutting tails of rodents and watching the next generation grow tails), which has nothing to do with Darwin’s concept of conditions of existence. Nonetheless, evolutionary biologists in general followed the line of the ‘all sufficiency’ theory and ignored Darwin’s conditions of existence, which in other words means the environment. Natural selection has a weak predictive power as it is based on random events. However, the conditions of existence have, by contrast, strong predictive powers that can be tested. The environmental views of two of the greatest evolutionists, Lamarck and Darwin, have been consistently ignored by most evolution theorists who came after them, continuing for over 200 years. Looking at the fossil record through the eyes of Darwin’s conditions of existence, not to mention the recent changes in height and shape over the last century, it is possible to draw important conclusions about the past and predictions of the future. With new knowledge of epigenetics, it is perhaps time that Darwin’s conditions of existence were given a second hearing.