While we have all heard how important exercise in order to prevent obesity, a new study shows that eating habits may in fact play a larger roll.
A study of the Hadza tribe, who are hunters and gatherers, suggests the amount of calories we need is a fixed human characteristic. This study suggests that the obesity epidemic is due to poor food choices instead of lack of an active lifestyle. The harsh reality is that one in 10 people will be obese by 2015. Nearly one in three of the worldwide population is expected to be overweight, according to figures from the World Health Organization.
The Western lifestyle is thought to be largely to blame for the obesity “epidemic”. Daily energy expenditure might be an evolved trait that has been shaped by evolution and is common among all people and not some simple reflection of our diverse lifestyles” Various factors are involved, including processed foods high in sugar and fat, large portion sizes, and a sedentary lifestyle where cars and machines do most of the daily physical work. The relative balance of overeating to lack of exercise is still up for debate.
Some experts have proposed that our need for calories has dropped drastically since the industrial revolution, and this is a bigger risk factor for obesity than changes in diet. A study published in the PLoS ONE journal tested the theory, by looking at energy expenditure in the Hadza tribe of Tanzania. Members of the tribe hunt animals and forage for berries, roots and fruit on foot, using bows, small axes, and digging sticks.
A team of scientists from the US, Tanzania and the UK, measured energy expenditure in 30 Hadza men and women aged between 18 and 75. They found physical activity levels were much higher in the Hadza men and women, but when corrected for size and weight, their metabolic rate was no different to that of Westerners. Researchers had assumed that hunter gatherers would burn hundreds more calories a day than adults in the US and Europe.
In the end, while this study was surprising, researchers are still stressing that BOTH diet and exercise are key components in not only fighting obesity but maintain overall health and wellness.