More articles Monday 12 August 2019 6:10pm
“Everything in moderation, including moderation,” says Geneticist and Author Dr. Giles Yeo.
Dr. Yeo discussed his book Gene Eating in an event chaired by journalist Ruth Wishart at the Edinburgh International Book Festival today, examining topics including fad diets, veganism and how our genetic makeup impacts weight loss.
Yeo says there are two factors the brain takes into account every time we eat. “Your brain needs to know two pieces of information in order to influence your food intake. First, it needs to know how much fat you have, and why? Because how much fat you have is how long you would last in the wild without any food, if food stopped today. And secondly, it needs to know what you have just eaten and what you’re currently eating.
“If you lose any weight, your brain hates it because it considers it a reduction in your likelihood of survival. So it will always make losing weight difficult. If anyone tries to sell you an effortless way to lose weight, they are lying.”
When queried about veganism being used as a tool for weight loss, Dr. Yeo said: “It’s now become mainstream because people think it’s healthier. So, the cold truth is we probably eat too much meat as a society. This is true. Okay, does this mean all of us need to suddenly become vegan? Well I think it suits some people and for some people, it’s something to do. I think all of us need to probably eat ten - twenty percent less meat or even something more rather than eat no meat at all, but I guess this is the point if the kernel of truth is being vegan will help you lose weight. Not because it’s magical, because you eat less calories.”
His new book examines how genetic predisposition comes into play with how humans, as individuals, digest and process food. He started off by saying “Body weight is not a choice. Now obesity just happens to be one end of the spectrum from being skinny and being average size. So, it’s a spectrum, okay, it’s not a choice. Now let me just caveat this, clearly it’s my choice if I choose to eat the cookie or not and I appreciate that, but remember we don’t gain weight overnight. We gain weight over a year, over a few months.”
“People think that when you gain weight, you gain fat cell. Okay, maybe you get more fat cells. This is not true. Fat cells are like balloons and they get bigger and they get smaller, and when we gain weight they get bigger, and when we lose weight, they get smaller. The safest place to store fat is in your fat cells as they do this because that's their professional job. It's when they're not in the fat cells, and they go into your muscles, your liver, other places, that's when you tilt into disease. But what’s interesting is, all of our fat cells expand to differing amounts individually.
“So when we carry too much fat we will become ill, but how much fat we can carry, that is going to be down to our individual genes.”
For those interested in finding out their genetic mapping for food digestion, Dr. Yeo offers two free solutions. “The first is very depressing, but if you actually just look at your parents, when you just imagine anything about your parents, their shape and size, the size of their bottom, also what diseases they have. That is free and far more predictive than any genetic testing. Second of all, if you have to lose the weight, if you are honest with your own failing behaviour, so for example, do I respond to stress by eating or not? Do I prefer chocolate, or what have you, then at least you have a fighting chance of controlling the environment you can control, meaning your household.
“So until we get to the point where genes can actually help in this prediction, I think look at your parents and be honest with your own feeding behaviour. I think those two things together are probably going to be quite effective.”