We know we should eat less junk food, such as crisps, industrially made pizzas and sugar-sweetened drinks, because of their high calorie content. These “ultra-processed” foods, as they are now called by nutritionists, are high in sugar and fat, but is that the only reason they cause weight gain? An important new trial from the US National Institute of Health (NIH) shows there’s a lot more at work here than calories alone.
It’s that time of year when many are trying, and some are failing, to live up to their New Years’ resolution of losing weight. Many of these probably include resolutions to be more physically active in striving for this goal. But first, there are some common misconceptions about exercise and weight loss that need to be addressed.
Breakfast, we are told, is the most important meal of the day. Over the last 50 years, we have been bombarded with messages extolling the health benefits of processed cereals and porridge oats. We are told breakfast helps us reduce weight by speeding up our metabolism – this helps us avoid hunger pangs and overeating later in the day.
Meal-replacement diets, where some meals are replaced with soups, shakes or bars, have been making a comeback. They first took off during the early days of space travel when the public became obsessed with the idea of a nutritionally complete meal in a single drink or bar. These products remained popular for most of the 70s and 80s, but gradually fell from favour as people began to question the health benefits of these diets.
It’s been one of the most astonishing changes in human anatomy. In just one generation, people all over the world have got a lot bigger. Although we’re also gradually getting a bit taller, the really big change has been in body fat. And while much of this is put down to lifestyle, some suggest that “obesity genes” mean it is easy for some people to gain weight and more difficult for them to lose weight
When you think about body fat, it’s probably white fat that comes to mind. That’s where our bodies store excess calories, and it’s the stuff you want to get rid of when you are trying to lose weight. But white fat isn’t the only kind of fat in the body – you also have brown fat and beige, or brite, fat, which can actually burn calories instead of storing them.