How much do genes affect your health?

Do you know people who can eat pizza and drink beer every day, yet have a slim physique? Or perhaps they even have "six pack abs" despite a less than ideal lifestyle?

While others have to train and eat healthy almost all the time to get the same result?

We all probably know a few of each kind of person.

So what is my point?

There can be big differences in how we respond to training and nutrition, with a lot of it depending on our genes.

Why does a high carbohydrate diet work for some people, while a high protein, low carbohydrate diet works well for others?

While some of it has to do with our activity level, much of it has to do with our genetics.

A person following a lifestyle that is not suited to their genetic makeup would end up with poor results, and a lot of frustration.

At my fitness centre in Singapore, I have a male client who weighs about 75kg, has sub 6 per cent body fat (veins popping out in his thighs and calves and a nice 6-pack of abs), is strong and has a very nice looking physique.

He eats only two meals of unhealthy food per day or sometimes one. He trains with average consistency, and he sleeps only 4-5 hours per night.

Most people who live a lifestyle like this would have 26 per cent of body fat (i.e. obese), and have less energy than a person with a bad hangover!

How come he can get away with that? Simple. Genetically, he is more gifted.

Such a person has a better ability to use carbohydrates instead of storing them as fat. They also usually have strong stress management systems, and a good ability to detoxify many harmful hormones and chemicals.

The rest of us probably need to do a lot more planning and training to get similar results. It can be done, but it just takes more love - love of being healthy, strong and fit.

At the Olympics, the world record holder in the 100m, Usain Bolt, was known to eat a meal of McNuggets before the race. This is by no means an ideal meal, but for a person of his ability, it's just fine. He won the gold medal of course.

Michael Phelps eats a high-refined carbohydrate, high-starch, 12000-calorie per day diet and wins multiple medals in Olympic swimming. (He also has long arms and flipper-like double jointed, big feet).

Not deterministic

But you have some control

But not to fear, genetics do not determine your destiny. You still have some control. Genetics (despite what some over-enthusiastic media reports claim) is not the only determining factor over your life.

Genes only express themselves (in other words, "turn-on") in the correct environment. If we create a good environment, good genes have a tendency to express themselves more, and bad genes express themselves less.

Here's an example.

Most of you know of Yao Ming, the Chinese basketball player who stands at an estimated 2.29m. He is married to a member of the China national women's basketball team.

If I asked you, do their children have the genes to be tall? The answer is "Of course!"

However, what if (for example) the child was brought up in a place where famine is a common occurrence. Would the child be tall? Or rather, would the child be as tall as his genes allowed him/her to be?

The answer is: "Of course, not."

The environment of malnutrition would not allow the full expression of the "tall" genes.

The same holds true for you and me. Your ancestors may have been obese, had diabetes, had high blood pressure, had cancer, had this and that. It may even be true that you have the genes for such diseases!

Cultivate good habits to combat 'bad' genes

But if you do your best to put your body in the right environment, the chance of such unfortunate illnesses happening to you can be greatly reduced.

It is hard for a bad gene to express itself in a well-nourished, well-exercised, emotionally healthy person with a positive outlook on life.

As one PhD scientist explained it, when you put yourself in a good environment, the parts of your genes that are "bad" and likely to cause problems are "skipped" when your body is reading the genes. This makes them unable to assert their bad influence on your health.

So, as in many things, action is way better than simply thinking or worrying about the problem! Maximise your health with good lifestyle habits and positive relationships and keep those bad genes from being read.

This article was contributed by Jonathan Wong, a personal trainer and weight loss coach. Coach Jon, as he is known to his clients, owns Genesis Performance Center, a private health and fitness centre that offers personal training and fitness bootcamps in Singapore. To find out more, visit