The truth about yo-yo diets
Have you ever, or do you know somebody who has been on a diet (usually some sort of restricted calorie intake diet), lost a lot of weight, then eventually put the weight back on again?
This process is called yo-yo dieting (due to the up-down-up-down nature of weight loss), and, according to recent research, can make you more overweight than when you started.
The thing is about low calorie diets isn’t that they don’t work….quite the opposite, they definitely do work….in the short term. You see it all of the time, ‘I’ve lost loads of weight over the last 5-6 weeks because I’ve been following the x or y diet’. The thing is that it is very difficult indeed to adhere to these sorts of diets in the long term. There are many reasons why this could be: the diet could be very low in an important macronutrient and the body could eventually crave that sort of thing or develop a malnutrition related condition. Fats and proteins make us feel full, so a diet that is low in both of these will make us feel hungry more often, etc. When people do fall off the wagon, they tend to overcompensate by eating more food than they did before they started the diet, which leads to further weight gain.
People’s relationship with food
The senses of taste and smell are directly linked to the limbic system in the brain, which is also the centre for emotion, meaning that humans intrinsically tend to have an emotional relationship with their food. Foods can trigger certain good or bad memories, which may be a reason why some people have more of a positive or negative relationship with food than others.
Because of this emotional relationship it is very difficult to dramatically change the diet in the short term. In particular, diets that promote a massive decrease in calories and diets that are very low in carbs.
Another thing about food: it tastes nice! Many people eat food because it tastes good, which is mainly due to two things: fat and/or sugar. So, a fad diet that takes out large amounts of fat may lead to the diet not tasting very nice and may affect adherence. This relationship between fat and sugar is also prevalent in ‘low fat’ foods. In general (although there are exceptions), foods that are naturally high in fat and have ‘low fat’ options, and these ‘low fat’ options tend to have high amounts of sugar (and sometimes salt) to compensate for the lack of taste due to the low fat content. Low fat options may also be challenging to cook with (anybody who have ever tried to melt ‘low fat’ cheese will know about this!).
Quick Results or a long-term solution?
There is little doubt that many diets work in the short term. There is a plethora of evidence that low carb, low fat and hypocalorific (very limited calories) make you lose weight in an 8-12 week period (insert one reference for each). However, in the long term, most people struggle to keep the weight off, which suggests that another approach may be needed.
Recent recommendations from British Dietetic Association (one of the few institutions that recommend things based on solid scientific evidence) state that weight loss should be a slower, more sustained process, suggesting that losing a pound or two of weight per week makes it more likely that you will then keep it off in the long term. Doesn’t sound good for anybody who wants to lose all that weight before holiday though….
One thing to consider is why do you want to lose the weight before THIS holiday, ie. Why do you need to lose all of the weight now? Is this going to be the last holiday you ever take? Would you rather look good in a photo now or live for longer and, in a while, look good in ALL YOUR PHOTOS?
There are also other things to consider, why do you not like the way you look at the moment? Are you comparing yourself to the cover models that are slashed all over our newspapers and TV screens? Are you worried about not looking good against your friends or peers?
It may be worth digging a little deeper and finding out why these feelings are present and maybe even help with the feeling of the ‘I need it now complex’.
The Bottom Line
Yo-yo dieting is not good for your health. People tend to lose weight then put on more weight, leading to a net gain in weight. This can become a cyclic problem and lead to both physiological issues linked with obesity (such as high blood pressure and an increased risk of cardiovascular disease) and psychological problems relating to body image, self-efficacy and relationships with food.
The safest way to lose weight is to lose it gradually over a sustained period of time by making small changes to your current diet. There is no magic wand cure and, although there are some diet companies doing some real good, anybody who claims to have the answer in the form of a quick fix is highly questionable.