Over a time span of more than 20 years scientists followed the food and lifestyle habits of more than 120,000 people and looked at what foods caused the worst weight gain. It comes with a surprise.
20 Years Of Habits
The study’s participants, who at the beginning of those 20 years had a normal body weight, gave their current weight every four years and also stated what foods they ate, if they smoked, how much time they spent in front of the TV and if they were into fitness. From that baseline calculated at the start, the scientists then looked at how changing nutritional and lifestyle habits influenced a person’s body weight.
Potatoes From Hell
Their results found the worst culprits for increased weight were products based on potatoes. For each one increased portion of 30 g of potato chips, 1.69 lbs (0.77 kg) extra came in after four years, while potatoes themselves led to an increase of 1.28 lbs (0.58 kg). Interestingly, there was a marked difference between fries and salted or mashed potatoes: fries lead to an increase of 3.3 lbs (1.5 kg), mashed or salted potatoes only to 260 g more.
Sugared soda pops brought 1 lb (450 g), while processed and unprocessed red meats led to 0.95 lbs (430 g) and 0.93 lbs (422 g) more weight. Daily desserts or sweets apparently had only a comparatively small effect: regular consumption led to 180 g more on the scale. These might put further dents in the armor of raw food and high protein diets, where carbohydrates are seen as major contenders in rising obesity rates.
Especially because on the other end of the spectrum, a higher intake of whole grains, and therefore carbohydrates, was associated with an average loss of 0.37 lbs or 168 g. Further foods mentioned in connection with weight loss were vegetables (-0.22 lbs, 100 g), fruits (-0.49 lbs, 220 g) nuts (-0.57 lbs, 260 g) and yogurt (-0.82 lbs, 370 g).
Too Much Or Little Sleep
To get the complete picture, let us also mention lifestyle factors outside of eating:
- every hour of watching television meant 0.31 lbs (141 g) more body weight
- people who had recently quit smoking, gained a whopping 5.17 lbs (2.3 kg)
- getting less than six or more (!) than eight hours of sleep resulted in increased weight as well
- physical activity of course had a positive effect: a decrease of 1.76 lbs (798 g)
Eat Nuts And Lose Weight?
Of course this doesn’t mean that you should now simply have some nuts to go along with your potato chips – it is the whole picture that counts.
Nuts have quite a bit of calories and only when they become part of a more conscious layout of food choices will consuming them have a positive effect. It is very likely that people who ate more nuts and lost weight also ate more vegetables and fruits.
Good And Bad Foods?
However, Dr. Frank Hu, the paper’s senior author, draws a drastic conclusion from the results:
These findings underscore the importance of making wise food choices in preventing weight gain and obesity. The idea that there are no “good” or “bad” foods is a myth that needs to be debunked.
I wonder how exactly Dr. Hu meant this. Is a food bad if we are likely to eat too much of it? Would it be good if it contains little nutrients but also little calories? Would it, on the other hand, be bad if it had many nutrients, but also many calories? The potato, for example, that in this study was associated with increased weight, is a very nutritious food.
A food per se doesn’t lead to increased weight gain, consuming more calories than you burn does.