What happened? Both groups lost weight, but after six months the women on the Palaeolithic diet had lost more, and their waists now measured less than those on the Nordic diet. It seemed as though this diet was better, but then things changed. After two years there was no difference in weight between the two groups. The only difference was in levels of the harmful blood fats, triglycerides, but even then they were at what would be considered safe, normal levels in the people on the Nordic diet too. Both groups found the diets difficult to manage and most people didn’t achieve the targets of eating the right amounts of each food group.

So, there’s no hard and fast evidence yet that we should be eating like cavepeople. It is of course unhealthy to eat a diet which mainly consists of highly processed foods like white bread and sugary cereals, but this doesn’t mean that all dairy products and grains need to be avoided unless you have a specific problem with them. In a three-week study from 2011 people found it hard to reach the recommended daily amounts of calcium, iron and fibre on the Palaeolithic diet. Not all studies are using exactly the same diet, though, which makes them hard to compare.

When it comes to losing weight, the advice is pretty dull – eat less and exercise more. Which is probably why any diet which claims to have found an alternative seems appealing, though. But, unfortunately, it seems that there’s still no magic bullet.

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