Do fad diets work?
Fad diets can deliver weight loss in the short term, but this is often down to losing lean muscle and fluid loss instead of body fat. It’s sustaining the loss which is the issue, says the British Dietetic Association (BDA). These diets can’t be followed long term as many people can’t stick with the rigid rules and limits.
“Quick fix diets also tend to focus on appearance driven results, rather than your long-term health and wellbeing”, says dietitian Jennifer Low, who specialises in disordered eating at her clinic. “They fail not because you lack willpower, but because they are set up to fail.”
What is the problem with dieting?
Crash diets are the gateway to yo-yo dieting, says behavioural change expert Sandra Roycroft-Davis. ‘People restrict, lose weight quickly, then regain — often more than they lost. Each cycle chips away at self-esteem and contributes to mental fatigue.’
‘Your mind sees restriction as a threat and retaliates with cravings, hunger, and emotional eating. It becomes a battle and one that willpower alone can’t win,’ she says.
TV presenter and author Dr Dawn Harper is not against a restrictive to kick start weight loss, especially if you have a health issue.
“Doctors often recommend a calorie restrictive diet for health reasons” she says. “If you have raised blood glucose and are prediabetic, for example, shifting weight can prevent you developing type 2 diabetes and its associated risks, such as heart disease and stroke. Following a lower calorie diet, such as The Fast 800 Programme by the late Dr Michael Mosley, or one of the other intermittent fasting diets, has been shown to put type 2 diabetes into remission.”
Under supervision, the ketogenic diet can help people with epilepsy who don’t respond to anti-seizure medication. It also has benefits such as lowering your heart disease risk. On the down side, there are side effects known as the ‘keto flu’ which can temporarily cause bad breath, headaches, dizziness and fatigue.
“If you do follow a fad diet to kick start your health journey, it’s best to return to a balanced style of eating. That doesn’t mean bringing back every processed food or refined carbohydrate on a daily basis, but it’s important you include nourishing foods, like plants and wholegrains.”
Dr Harper highlights that modern eating predisposes us to weight gain, but “nothing beats sticking to a well balanced diet for a long, healthy life.” In her book Live Well to 101, she provides plenty of practical lifestyle advice and achievable changes. ‘It can be as simple as structuring your plate so that the protein is the side dish and vegetables form the main part of the meal.’
What is the crash and crave cycle?
By drastically cutting calories or food groups we start to crave the foods we’re missing. ‘When you cut out foods containing sugar for example, you will want it more,” says Low. ‘And because you think it’s ‘bad’, once you give in to the craving you will end up eating lots of it.”
When people lose weight, they may attribute it to avoiding specific foods, like sugar or carbs. However, by focusing on including nutrient dense foods, you will live a healthy life that’s free from the constraints of food rules and, no doubt, notice improved mental health.
It’s important to know that on an extreme diet your body thinks it’s being starved, so your metabolism slows down to redress the deficit, which in turn reduces the rate you burn calories and your weight loss stalls.
“I’ve tried several fad diets over the years to shift holiday or Christmas weight. After two weeks on the South Beach Diet I nearly passed out with dizziness on the way to a meeting in Central London. I was forced to quit the diet and quickly craved the carbs I’d cut out. Of course, any weight lost went straight back on.
Research shows all diets can help you lose weight, it’s finding the one that works for you. My experience following the 5:2 Diet was more successful, as eating less on two days a week is much less restrictive. I lost the weight gradually and kept it off, and began building healthier meals with vegetables, wholegrains, lean meat and plant-based proteins. The main downside was fantasising about what to have for breakfast at the end of a fasting day.
So, what is the best way to lose weight?
Health experts generally agree the best way to lose weight is gradually, by following a healthy eating plan combined with adequate exercise. This means cutting around 500 calories a day from the recommended calorie daily intake of around 2,000 calories for women and 2,500 for men. Factor in the government’s recommended 150 minutes of exercise a week, including cardio such as running, cycling or swimming for fat burning, and you could lose 1-2lb a week. You’ll find advice about healthy eating on the NHS website, including how to get started.
‘Successful weight loss is about making small lifestyle changes that you can see yourself sticking to next week, next month and next year,’ says Dr Harper. ‘I have often said that there is no such thing as a bad food, but there are plenty of bad diets. A small piece of chocolate, as an occasional treat, is not going to make you fat, but a whole bar every day probably will,’ she says.
It’s important to remember that we’re all human, says Dr Harper. ‘We will have days when we break our healthy regime, but it’s important not to let that one day lead to throwing in the towel and undoing all the good you’ve achieved. ‘Just see it as a blip, pick yourself up and get back on the wagon,’ she says.
Roycroft-Davis has seen the damaging effects of crash dieting. ‘The weight loss industry is full of promises, but many are built on quick fixes that leave people stuck in a cycle of self-blame, restriction and rebound,’ she says.
So, she created Slimpod, a programme rooted in behavioural science, to help people change their habits around food. ‘Instead of relying on rules, willpower, or calorie counting, we help people create lasting change by changing habits from the inside out, which results in a natural shift without guilt or obsession.”
Now try…
50 ways to lose weight
How to start a well-balanced healthy eating plan
Read our round-up of popular diets, including the 5:2 and Atkins
Find out more about healthy weight-loss
Try our ketogenic recipes
All health content on goodfood.com is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. If you have any concerns about your general health, you should contact your local health care provider. See our website terms and conditions for more information.
