Many people believe that in order for a diet to be effective it just needs to help you lose weight. However, a diet didn’t work if you put the weight back on. You hear so many people talk about how they did a diet and it worked so well, however they slacked off, put the weight back on and really need to get back on track and get back on that ‘diet’. Those people are missing the point - they put the weight back on… therefore the diet did not work!
But more to the point of why a ‘diet’ doesn’t work. When people talk about diets they usually are talking about something that has an end point. They are on a diet to try get to a magical number, envisaging that when they reach this number they will be able to resume their way of eating as normal and all will be well. Wrong. The unfortunate truth of it is that when most people lose weight they will gain it back (and sometime more) within 1-5 years.
So why does this happen?
Going on a calorie-deprived diet relies solely on the theory of calories in vs. calories out. Now this works well, to an extent. The problem with chronic calorie deprivation and ‘quick fix’ weight loss is that it can alter your metabolism and the body’s ability to regulate fat storage/loss.
The Biggest Loser study is a great example of this. The study followed contestants from the wrap up of the show to 2015- 6 years on. They looked at body weight, fat percentage, resting metabolic rate and hormones (1).
After 6 years 13 of the 14 subjects had regained a significant amount of weight, whilst 4 of those are heavier now than what they were before they went on the show!
The average resting metabolic rate (RMR) of the participants was 2,607 kcal/day prior to the competition and dropped to 1996 kcal/day by the 30-week wrap up. Despite majority of the participants regaining a significant amount of weight, the mean RMR 6 years on was still only 1903 kcal/day! (1)
Put simply, the researchers found that their metabolisms were burning 500 fewer calories each day than expected given their new weight. No wonder they all had a tough time keeping the weight off!
Another interesting find was the significant reductions in the hormone leptin. Leptin is coined the ‘satiety hormone’ and is responsible for the long-term regulation of energy balance, supressing food intake and thereby inducing weight loss (2). Before the competition began the mean leptin, levels were around 41.14ng/mL. Post competition these levels had plummeted to an average of 2.56ng/mL (1). At the 6-year mark (and with the significant weight gain) leptin levels had only rebounded to around 60% of what they were.
This is thought to be due to thousands of years of survival tactics the body has developed to stop us from starving to death (3)- very handy back then but not so much now that we have an abundance of food all around us.
As depressing as this all sounds, there are strategies you can put into place that could help to minimise all these negative effects of weight loss.
1. Consult a qualified nutrition professional
Embarking on a severely calorie restricted diet you got from Woman’s weekly is probably not going to be your best bet. Consulting a nutrition specialist can save you a LOT of time, energy and money. They will take away the guesswork and allow you to embark on a plan that is going to work for life. Ensure this person is qualified (e.g. a registered nutritionist or dietician) so you get the best results!