Do these fruits help weight loss?

Following on from my last blog post, I wanted to look at the claims that some fruits help weight loss. The first of these is linked to one of the most extreme ‘mono-diets’ – the banana diet involves eating thirty bananas in a day and nothing else. There are people who insist it has great health benefits – and if you had to choose just one food to eat, there are many worse choices than the banana because it does contain many of the vitamins and minerals you need for good health. Personally I wouldn’t recommend such a restricted diet, though.

But do bananas live up to their reputation as a superfood? It’s commonly known that they’re a great source of potassium. But another mineral they also provide in high levels is magnesium. Magnesium is vital for hundreds of processes within the body. It is critical for energy production and healthy nerve function, and it also promotes muscle relaxation and helps the body’s production and use of insulin. But it also helps with calcium absorption, and research has shown that the correct balance between these two minerals is important for weight loss.

They’re also high in fibre, and, while they’re slightly higher in calories than other fruits, at around 92 calories for a medium sized banana they’re still a healthy, low-calorie choice. So in short, the banana definitely does live up to the hype.

So how about another fruit that also has it’s own rather extreme diet? Research has shown that eating half a grapefruit before every meal can lead to greater weight loss, but there are other reasons why this fruit is a good one to include in your diet. Grapefruit is well known in many diet plans, particularly for breakfast. But it seems there’s more to this fruit than simply low calories (42 calories per 100g/3.5 oz) and vitamin C. Surprisingly, grapefruit is a good source of fibre, and for reasons that aren’t yet fully understood, compounds in grapefruit reduce insulin levels. Low levels of insulin mean your body can more efficiently use food for energy rather than storing it as fat, thus helping with weight loss.

Other research claims that the smell of grapefruit can affect liver enzymes, which apparently reduces cravings and helps with weight loss. I’m not convinced by this one, myself. It seems more likely that starting your day off with half a grapefruit means that you eat less breakfast and thus take in less calories as a result…but I’m certainly not going to knock something that offers half your daily vitamin C requirements in just half a fruit!