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Nutrition

Diets: the good the bad and the ugly

Billions of pounds are spent on slimming each year, but is calorie counting really the answer to losing weight – and keeping it off? We take a look at some of the latest trends.

With obesity levels steadily growing, the global weight-loss industry is currently estimated to be worth £220 billion*. Like so many things, diets go in and out of fashion, and magazines are full of the latest celebrity to follow this or that fad. Before embarking on a weight-loss regime, however, it's important to understand the potential health implications.

“Fad diets or crash diets that involve simply changing your diet for a few weeks may cause you to lose weight to begin with, but much of this will be water loss, and they are unlikely to lead you to a healthy weight in the long term,” says nutrition scientist Sarah Coe, at the British Nutrition Foundation. “They are generally quite difficult to maintain due to being quite restrictive, and could lead to cravings for high-fat and high-sugar foods.”

By banning wheat, carbs or dairy, for instance, mealtimes are unlikely to be sufficiently balanced. “If you cut out a food group from your diet, this makes you more likely to not be getting all of the important nutrients that your body needs to function properly,” says Sarah.

Take low-carb diets, for example. “These are normally high in protein and fat. A high protein intake could affect bone and kidney health, and too much saturated fat in the diet can raise your cholesterol and increase your risk of heart disease and stroke, so this type of diet shouldn’t be followed in the long term. Low-carb diets can also cause some unpleasant side-effects – for example, bad breath or constipation.”

Diets in the news

Paleo: The “cave man” or hunter-gatherer diet relies on the ingredients available to our Palaeolithic ancestors. The emphasis is on meat and fish, with high-fibre non-starchy vegetables – and no processed food.

5:2: With intermittent fasting (IF), you consume 500 calories (or 600 kcal for men) two days a week and eat normally for the other five days. It has gained a huge amount of support, including from TV presenters Phillip Schofield and Dr Michael Mosley. IF is said to promote a number of health benefits but further scientific analysis is needed.

Ancient grains: With wheat and gluten slipping from favour, some people are introducing quinoa, millet, chia seeds, spelt and buckwheat into their diets instead. Angelina Jolie is said to swear by the health-giving properties of raw seeds and nuts.

Alkaline: With Victoria Beckham as a fan, the theory here is to keep the body's pH at between 7.35 and 7.45. Alkaline-promoting foods including fruit and vegetables, tofu and certain legumes are in. Acid-promoting dairy, meat and processed foods are out.

Vegan: There's nothing new about avoiding animal products, however, Beyoncé and Jay-Z made it newsworthy again by going on a 22-day vegan health kick. Vegans may need to supplement with B vitamins and essential fatty acids.

Tried-and-tested weight loss

There's no one-size-fits-all approach and individuals should choose a diet to suit their preferences and lifestyle. “The best way to lose weight is to be physically active on a regular basis, whilst following an energy-reduced, balanced diet that contains lower fat products, wholegrain foods and lots of fruits and vegetables,” says Sarah Coe at the British Nutrition Foundation. “You should also include a source of protein – e.g. chicken, lean meats, fish, pulses or soya – with each meal, as protein can keep you feeling fuller for longer.

“Keep an eye on what you’re drinking, too, as drinks also contribute to calorie intake – so opt for water or diet drinks rather than sugar-rich or alcoholic beverages.”

Further reading

The NHS Choices website has some useful information about weight-loss myths to help you avoid the common pitfalls. There is also the Eatwell plate which is a really useful reference tool for planning balanced meals.

Visit our healthy eating hub for more articles about diet and nutrition.

 

*Figures accurate for 2017