A handful of nuts a day: small habit, big difference?

TLDR

• A handful of unsalted nuts a day (around 15 to 25 grams) is one of the simplest healthy habits in your kitchen.
• Large cohort studies link eating nuts regularly to a lower risk of cardiovascular disease and early death.
• Nuts are high in calories, but studies generally show no weight gain with a normal portion.
• Choose unsalted, either raw or dry-roasted. Salted and sugar-coated versions are best left on the shelf.

For a long time I thought nuts were “fattening”. Something for the bowl next to the drinks, with a pint of lager on the side. But once I got into nutrition and longevity, nuts kept turning up in the research. Time to look into it properly.

What the research says

A large analysis in the New England Journal of Medicine (Bao and colleagues, 2013) followed more than 100,000 American health professionals for decades. Those who ate nuts almost every day had a lower risk of death than those who never ate them. A dose-response meta-analysis in BMC Medicine (Aune and colleagues, 2016) reached a similar conclusion: around 20 grams a day went hand in hand with less cardiovascular disease, and eating more added little extra.

In the PREDIMED study as well, a randomised trial of a Mediterranean diet supplemented with nuts, the number of cardiovascular problems was lower than in the control group (Estruch and colleagues, 2018). So nuts are no miracle cure, but they are a strong part of a good eating pattern. That ties in nicely with what I wrote about the green Mediterranean eating pattern.

Why nuts score so well

• Unsaturated fats that help lower your LDL cholesterol when they replace saturated fat.
• Fibre, magnesium and vitamin E.
• Plant protein, handy if you eat less meat. See also my piece on plant proteins.
• Walnuts also provide some plant-based omega-3 (ALA).

And the calories?

A handful of nuts is easily 120 to 180 kcal. Yet studies generally show no extra weight gain when people add nuts to their diet. They are filling, and part of the fat isn’t fully absorbed. It is still a matter of a handful, though, not half a bag in front of the telly.

How I make it a habit

• On my salad or soup: a handful of roughly chopped walnuts.
• Stirred into my yoghurt or porridge in the morning.
• In a stir-fry with cashews, together with wholegrains and legumes.
• A small tub in my bag instead of a biscuit from the vending machine.

Practical Engy tip

Weigh out 20 grams once, so you know what a handful looks like. If you have a nut allergy, seeds such as pumpkin or sunflower seeds are sometimes an alternative, but discuss that with your doctor.

Sources (selection)

• Bao Y et al. (2013). Association of nut consumption with total and cause-specific mortality. New England Journal of Medicine, 369, 2001–2011.
• Aune D et al. (2016). Nut consumption and risk of cardiovascular disease, total cancer, all-cause and cause-specific mortality: a systematic review and dose-response meta-analysis of prospective studies. BMC Medicine, 14, 207.
• Estruch R et al. (2018). Primary prevention of cardiovascular disease with a Mediterranean diet supplemented with extra-virgin olive oil or nuts. New England Journal of Medicine, 378, e34.
• Vlaams Instituut Gezond Leven. De voedingsdriehoek: noten en zaden.