What does this indicator tell us?
Abstract It has long been suspected that the relative abundance of specific nutrients can affect cognitive processes and emotions. Newly described influences of dietary factors on neuronal function and synaptic plasticity have revealed some of the vital mechanisms that are responsible for the action of diet on brain health and mental function.
Several gut hormones that can enter the brain, or that are produced in the brain itself, influence cognitive ability. In addition, well-established regulators of synaptic plasticity, such as brain-derived neurotrophic factor, can function as metabolic modulators, responding to peripheral signals such as food intake.
Understanding the molecular basis of the effects of food on cognition will help us to determine how best to manipulate diet in order to increase the resistance of neurons to insults and promote mental fitness. Although food has classically been perceived as a means to provide energy and building material to the body, its ability to prevent and protect against diseases is starting to be recognized.
In particular, research over the past 5 years has provided exciting evidence for the influence of dietary factors on specific molecular systems and mechanisms that maintain mental function.
For instance, a diet that is rich in omega-3 fatty acids is garnering appreciation for supporting cognitive processes in humans 1 and upregulating genes that are important for maintaining synaptic function and plasticity in rodents 2.
In turn, diets that are high in saturated fat are becoming notorious for reducing molecular substrates that support cognitive processing and increasing the risk of neurological dysfunction in both humans 3 and animals 4.
Although these studies emphasize an important effect of food on the brain, further work is necessary to determine the mechanisms of action and the conditions for therapeutic applications in humans.
Over thousands of years, diet, in conjunction with other aspects of daily living, such as exercise, has had a crucial role in shaping cognitive capacity and brain evolution BOX 1.
Advances in molecular biology have revealed the ability of food-derived signals to influence energy metabolism and synaptic plasticity and, thus, mediate the effects of food on cognitive function, which is likely to have been crucial for the evolution of the modern brain.
The newly discovered effects of food on cognition are intriguing for the general public, as they might challenge preconceptions, and they attract substantial interest from the media.
The fact that feeding is an intrinsic human routine emphasizes the power of dietary factors to modulate mental health not only at the individual level, but also at the collective, population-wide level. Here I discuss the effects of both internal signals that are associated with feeding and dietary factors on cell metabolism, synaptic plasticity and mental function FIG.
Throughout I use the term cognition from a neurobiological perspective, to refer to the mental processes that are involved in acquiring knowledge and to the integration of these processes into the conscious aspect of emotions, which influences mood and has psychiatric manifestations 5.
Box 1Feeding as an adaptive mechanism for the development of cognitive skills Open in a separate window Adaptations that facilitated food acquisition and energy efficiency exerted strong evolutionary pressures on the formation of the modern brain and the energy-demanding development of cognitive skills.
For example, the wildebeest annually travels hundreds of miles to find feeding grounds in the savannah, a behaviour that requires fully operational and complex navigational, defensive and cognitive conducts for survival.
The function of brain centres that control eating behaviour is integrated with those of centres that control cognition FIG. For instance, animals that eat a potentially poisonous meal develop a perpetual aversion to its flavour through complex mechanisms of learning and memory that involve the hypothalamus, the hippocampus and the amygdala In turn, pleasant memories of foods have been related to brain pathways that are associated with reward Abundant paleontological evidence suggests that there is a direct relationship between access to food and brain size, and that even small differences in diet can have large effects on survival and reproductive success Larger brains in humanoids are associated with the development of cooking skills, access to food, energy savings and upright walking and running ; all of these features require coordination with cognitive strategies that are centred in successful feeding.
Dietary consumption of omega-3 fatty acids is one of the best-studied interactions between food and brain evolution. Docosahexaenoic acid DHA is the most abundant omega-3 fatty acid in cell membranes in the brain ; however, the human body is not efficient at synthesizing DHA, so we are largely dependent on dietary DHA The fact that DHA is an important brain constituent supports the hypothesis that a shore-based diet high in DHA was indispensable for hominid encephalization.
Indeed, archeological evidence shows that early hominids adapted to consuming fish and thus gained access to DHA before extensive encephalization occurred. The interplay between brain and environment is ongoing. Over the past years, the intake of saturated fatty acids, linoleic acid and trans fatty acids has increased dramatically in Western civilizations, whereas the consumption of omega-3 fatty acids has decreased.
This might explain the elevated incidence of major depression in countries such as the United States and Germany see figure, part b Part b of the figure reproduced, with permission, from REF.Environment and intelligence research investigates the impact of environment on intelligence.
In measuring intellectual capacity, The results indicated that there were no effects of under-nutrition on intellectual development.
However, many studies since have found a significant relationship and a meta-analysis by Shenkin and colleagues. The University of Arizona (UA) is the flagship institution in the State of Arizona and offers graduate programs in more than areas of study.
Graduate programs of study are described here in our Graduate Catalog and Program Descriptions. In the context of nutrition, studying the influence of macular xanthophylls in relation to different constructs of intelligence may provide insights into the value of lifetime dietary consumption of lutein and zeaxanthin rather than the acute effects of nutrients on preventing age-related decline [24,26].
Nutrition is the science that interprets the interaction of nutrients and other substances in food in relation to maintenance, growth, reproduction, health and disease of an organism.
It includes food intake, absorption, assimilation, biosynthesis, catabolism, and excretion. Roadmap for Nutrition in South Africa - 7 Department of Health Moderate acute malnutrition: Also known as wasting, is defined by a weight-for-height indicator between -3 and . Disclaimer: This blog post covers only a fraction of what's wrong with "The China Study." In the years since I wrote it, I've added a number of additional articles expanding on this critique and covering a great deal of new material.
Please read my Forks Over Knives review .