Improper diet is a risk factor for a number of diseases. However, the exact effect of different components of food may depend on a person’s genetic make up.
Nutritional genomics or nutrigenomics is the study of how different foods can interact with particular genes to alter a person’s risk of developing diseases and how individual genetic differences can affect the way we respond to nutrients. This means that it is not a question of whether your genes are good or bad, but rather how they interact with your environment.
The science of nutrigenomics also studies how genes, diet and disease interact to create health disparities for certain human populations that evolved from different geographic locations. For example, African American men have a 60 per cent higher risk of being diagnosed with prostate cancer than do Caucasian men. Half of all adult Pima Indians in the United States have type 2 diabetes, compared with 6.5 per cent of adult Americans of Caucasian descent.
Recent studies in Indians living overseas have shown a great potential for CHD in people of this subcontinent. They run just about the highest risk of heart attack and death compared to all other ethnic groups and races.
So far, modern nutrition and medicine have not worked on designing diets or medicines according to different ethnic groups or body types. Scientific wisdom is based on the premise that what works for one should work for most. It does not factor in individual differences. On the contrary, alternative/traditional systems believe that individuals are different and traditional therapies such as Chinese medicine, Unani, Ayurveda and Homeopathy have been formulated according on this premise. This could probably be an explanation of why one of the largest scientific trials on homeopathy failed to prove its efficacy. Nutrigenomics integrates this gap — studying genetic profiles and customising nutrients and foods according to the DNA.
The nutrigenomics effort seeks to identify genes controlled by nutrients and other naturally occurring chemicals in food and to study how some of these genes can tip the balance between health and disease.
Nutritional genomics helps individuals to better manage their health and well being by precisely matching their diets to their unique genetic make up.
In the USA, there are claims you can make your children more intelligent by customising their diet according to their genetic make-up… There is also the ‘DNA diet’, which claims you can lose weight, tone up and even live longer by following advice based on analysis of your DNA.
So far, evidence on the interaction of nutrients, genetic variations and health implications is uncertain. In fact, according to US Government Accountability Office (GAO), nutrigenetic tests “may mislead consumers by promising results they cannot deliver” and issue medical predictions that may either needlessly alarm or in some cases, falsely assure, consumers about their health.
However, this may well be the road ahead for personalised dietary intervention based on knowledge of nutritional needs, nutritional status and genes to prevent, mitigate or cure chronic diseases.