4 reasons why you shouldn't follow the latest diet

Goji berry

It’s New Year and we’re surrounded by new diets making big promises. But don’t believe the hype, says Sarah Brealey.

1. You could lose more cash than weight

Fashion affects the foods we eat as much as the clothes we wear. Peak ‘season’ is January, when the media bombards us with the latest diets for a slimmer new you.

For the diet industry, it’s an easy sell, with more than 65 per cent of women and 44 per cent of men trying to lose weight each year. We’re happy to hear about new diets, especially if we failed to lose weight the year before.

“We all like to have what is newest or the thing that promises more,” said Dr Angela Madden, Subject Group Lead for Nutrition and Dietetics at the University of Hertfordshire and a dietitian for more than 30 years.

The big winner is the UK diet industry, which is worth an estimated £2bn a year. Recent research from the US suggests demand for specific diet products is declining, while sales of free-from foods (such as gluten-free) have surged. The UK free-from market doubled in value between 2009 and 2014 and is predicted to keep growing significantly. 

Diet statsThere is no guarantee that either approach promotes long-term weight loss, with some estimates suggesting the typical diet lasts only 19 days. Fad diets fail because they can be hard to stick to.

Dr Laura McGowan, Chartered Psychologist, Research Fellow at Queen’s University Belfast and former Executive Director of the charity Weight Concern, said: “Every now and then, a miracle food or fad diet is announced that will reportedly help you lose weight effortlessly.

“They do not work, and certainly not in the long term. Some are based on scientific evidence that has been misreported, distorted or used out of context. Others are simply silly and potentially dangerous.”

Dr Madden added: “There are no magic diets. When someone is trying to lose weight, it is really important to assess them as an individual and address the issues from their perspective. It is about what works for you and what fits in with your lifestyle. The real problem is that many new diets haven’t been tried and tested over the long term.”

Some diets can have negative health consequences, particularly if you’re living with a condition such as high blood pressure or diabetes. Even if you do lose weight in the short term, you may put that weight back on if you return to old eating habits.

2. Superfoods may just be superfads

A healthy diet doesn’t have to be new or expensive

Dr Angela Madden

Superfoods are dictated by the whims of fashion too. There is no scientific consensus on what a superfood actually is.

Dr Madden says: “Superfood is a lovely term, but people should be eating a range of foods rather than focusing on one or two foods. Blueberries, for example, are often promoted as being a superfood. Like many foods, they have lots of benefits, but they are not going to solve all  of our dietary problems.”

Many so-called superfoods are relatively expensive - like goji berries, for example (pictured above). But as Dr Madden explains: “Cheaper vegetables like carrots, onions and cabbage have lots of health benefits too. The best thing is to have as wide a range as possible.”

3. Small changes are better than extreme diets

Evidence suggests making small changes gradually is best – in contrast to the sudden major changes of fad diets. The exact length of time varies across studies but UCL researchers have suggested it typically takes 66 days to form healthy habits.

Diet statsDr Madden said: “A healthy diet doesn’t have to be new or expensive. Just eating lots of fruit and veg, wholegrains, lean protein and dairy products such as milk and yoghurt will provide you with the nutrients you need and help control your weight.”

4. Portion sizes are important too

A new large-scale review of evidence shows larger portions encourage weight gain. The research, carried out by the University of Cambridge, suggests eliminating larger portions from the diet could reduce energy intake by up to 16 per cent among UK adults (and 29 per cent among US adults).

Dr Gareth Hollands, who co-led the review, said: “Helping people to avoid ‘overserving’ themselves or others with larger portions of food or drink by reducing their size, availability and appeal in shops, restaurants and in the home is likely to be a good way of helping people reduce their risk of overeating.”

Dr Madden said: “Being aware of the problem is the first step. New Year is a great time to make new efforts to eat healthily.” 

More useful information