It can be hard to get through the day without a snack or two, and all too often those snacks come in the unhealthy form of biscuits, cakes or crisps.
A handful of nuts, however, could curb those snack-cravings - and boost your health at the same time.
Not only will their concentrated protein content help you feel fuller for longer, but they could protect you from a whole host of illnesses.
A new study has found that patients with prostate cancer who consumed nuts five or more times a week after diagnosis, had a 34% lower rate of mortality than those who ate nuts less than once a month.
And last year, a Dutch study found a link between daily nut consumption and a reduced chance of dying from several chronic diseases, including cancer and heart disease.
Nuts are packed with protein, fibre and important vitamins and minerals, including - in differing proportions depending on the type of nut - calcium, iron, zinc, magnesium, vitamin E and B vitamins and selenium, the powerful antioxidant thought to help fight cancer, and which may also play a role in combating infertility, dementia and low thyroid function.
Nuts have a high fat content, but it’s the ‘healthy’ type - unsaturated - which is thought to help lower ‘bad’ LDL cholesterol levels.
Of course, not all nuts are created equal - a packet of roasted, salted nuts is not the same ‘healthy snack’ as some plain, raw almonds, for example, and d ieticians advise avoiding nuts that are packaged, salted or roasted in oil or honey; instead, eat them raw or dry-roasted.
Although the recent Harvard study found death rates among men with prostate cancer were more than a third less when they ate nuts regularly, it didn’t conclude that eating nuts actually helped prevent men from getting prostate cancer in the first place. However, other studies have suggested nuts - particularly walnuts - may help prevent, or at least delay, some types of cancer, including breast, prostate and colorectal.
Another Harvard study of 75,680 women last year found those who consumed a 28g serving of nuts two or more times a week, had a 13% lower risk of colorectal cancer compared to those who rarely ate nuts, while a Mexican study suggested that eating large amounts of peanuts, walnuts or almonds over a lifetime meant women were two or three times less likely to develop breast cancer.
Nicola Smith, senior health information officer at Cancer Research UK, points out that while some studies have found health benefits from eating nuts, it’s difficult to disentangle other factors that may be playing a role.
“It may be that people who eat lots of nuts are healthier in general,” says Smith. “Scientific research doesn’t show that any single ‘superfood’ has a particular benefit for preventing cancer. But we do know that eating plenty of fibre, fruit and vegetables, and less salt and red and processed meat reduces cancer risk.”
Many studies have identified a link between eating nuts and reduced risk of cardiovascular problems. Harvard research found men who ate nuts at least twice a week over a year had a 47% lower risk of sudden cardiac death and a 30% lower risk of dying from all types of coronary artery disease.
Plus, previous Harvard research involving more than 86,000 women found that over a 14-year period, those who ate at least 5oz of nuts per week were 35% less likely to suffer heart attacks than women who ate less than 1oz a month. An analysis of other risk factors, such as diet, lifestyle and existing health conditions, including blood pressure, cholesterol and family history, showed the protective power of nuts couldn’t be explained away.
One theory is that the beneficial effect on cardiovascular health may be linked to the effect nuts have on cholesterol - researchers in Canada compared three low-fat vegetarian diets and found that while they all produced lower cholesterol levels, the diet that contained 2.2oz of nuts a day reduced ‘bad’ LDL cholesterol by 30%. It’s also thought that nuts lower insulin resistance, so they help reduce the incidence of diabetes and inflammation.
They might be good for you but, like many foods, it is possible to have too much of a good thing, and nuts can be quite calorific because of their fat content, containing 160-200 calories per 28g serving, depending on the type of nut.
A 28g serving is the equivalent of a handful - or about 14 shelled walnut halves; 24 shelled almonds; 16 cashews; 28 peanuts, or 45 pistachios.
“As a substitute for foods high in saturated fat and sugar, nuts can be a good choice,” says British Heart Foundation dietician Victoria Taylor. “The high protein and fibre content makes them a satisfying snack and they contain nutrients such as vitamin E, potassium and magnesium. But watch your portion sizes.”
Find it hard to stop at one handful? Taylor suggests that people who find it hard to stop eating nuts after a handful should opt for varieties that need shelling, as having to crack them open takes more time, which means less time for eating. “If you keep an eye on portion sizes and avoid unhealthy additions like salt and sugar, nuts can be a healthy choice between or with your meals.”