DNA based Diets

There are widely accepted recommendations for diet and health, but the truth is we all vary in our response to food. Why is it that couch potato Joe can eat take out fish and chips weekly and have good cholesterol, while Bob’s cholesterol, who exercises several times a week, and has a veggie based diet mind you, is sky high? It certainly gives meaning to some ‘food for thought.’ We hear about the latest in health and nutrition all the time, but have you ever asked yourself why one week to the next the info can often be polarizing? Last week studies said coffee was good for heart health, this week it’s not. The mystery behind the door here is our genetics. The science of our genes, our hereditary and the variation this can have within oneself, and members of same and differing species. Genetics, specifically nutritional genomics, is the reasoning for differences in the above scenarios. It’s a fairly new science which allows us to understand how our genes affect the way we respond to the foods, beverages and supplements we consume.

Nutrient-gene interactions are very complex. Both our genes and the nutrients we eat can cause different responses in different people (our example of fish and chip loving Joe and Bob above) and even different responses in the same individual who changes the types of food they eat. The link between food and health is well documented however people still struggle to find the right balance between energy intake and output. Take type 2 diabetes. It’s largely preventable with an adjustment of lifestyle factors, including diet. Not only is it a fairly populous condition here in NL, but it can have a genetic basis too. (It’s thought about one of two people have the ‘risk variant’ in their genes for type 2, but in NL it could very well be higher than that). Whole grains that have a low glycemic index (i.e. favorably affecting our blood sugar) may contribute to a protective effect against type 2 diabetes. Their consumption is thought to reduce the risk of not only type 2 but health disease too. One meal of white bread, bagels, potatoes and short –grain white rice won’t cause genetic changes overnight, but with time and repeated exposure to specific dietary components, genetic messages can be alarmed or put to sleep to enhance health or increase risk of disease. So if today you could find out that you are one of the two who has a higher genetic potential for type 2 diabetes would you want to know? If so, would you take proactive steps to try and change it? It’s probably a question you’ve never asked yourself before, but the way things are going it’s a good one to start considering.

Dietary patterns are strongly linked to seven of the top ten causes of sickness and death in North America. Genetic disorders that can be related to food are numerous. Genetic variants have been associated with above mentioned type 2 diabetes, obesity, cardiovascular diseases, osteoporosis, some autoimmune diseases and cancers especially of the colon, stomach and breast. Let’s jump back to the coffee example. When it comes to coffee consumption and whether or not there is a heart health benefit the answer is actually yes, no and maybe. Due to our genes, some of us are "rapid" or “slow” caffeine metabolizers. Coffee consumption is associated with an increased risk of heart attack only in those individuals who are slow caffeine metabolizers, and in those who are rapid metabolizers it has the opposite effect. There are many more examples with the above conditions and food substances like the B vitamin folate, vitamin C, sodium, saturated and omega-3 fats. Considering the top causes of sickness and death, the fact many of them are diet related, the reality that not only can diet influence our genes but we can also manipulate out diet for better health based on our genes- one only needs to connect the dots to see that the future for diet and health is headed towards individual genetics.

As seen in The Telegram August 20, 2012