Nuts: Are they linked to weight gain?

5th Apr 2024

Nuts are another must-have in our pantry. Beyond an easy snack, they are sometimes the missing element in a dish, adding texture to your favourite sauces, curries and salads. Here are 5 things to know about nuts!

Key points

• 1. Most ‘nuts’ aren’t technically nuts
• 2. They are nutritional treasures
• 3. Eating nuts can support better health
• 4. Go for ~1 handful of mixed nuts
• 5. They might be what your dish is missing…
• Recipes to try

1. Most ‘nuts’ aren’t technically nuts

Many foods we call nuts, like walnuts, pistachios and almonds, are actually the seeds of drupe fruits. In the botanical world, a nut is a dry fruit with one seed covered by a hard shell that doesn’t split open when it matures. We’re talking chestnuts, hazelnuts and acorns. But here’s where it gets interesting: in the culinary world, the definition is much looser and includes any edible kernel surrounded by a shell, which is why many edible seeds are popularly called nuts.

2. They are nutritional treasures

Nuts contain a myriad of nutrients and health-promoting bioactive compounds, including…

• Dietary fibres
• Minerals, such as magnesium, potassium and copper.
• Vitamins, such as vitamin E, vitamin B6, niacin, and folic acid.
• Plant protein, ranging from ~3 to 10g per 28g portion. The highest sources of protein tend to be hemp seeds, pumpkin seeds, almonds, pistachios and cashews.
• Healthy fats, such as monounsaturated and polyunsaturated fats. Some nuts, like walnuts, are a rich food source of α-linolenic acid, a plant-based omega−3 fatty acid.
• Phytosterols and phenolic compounds, especially flavonoids and phenolic acids.

3. Eating nuts can support better health

Will eating nuts make you gain weight? The worry about nuts and their high energy density has been around for a while. But current evidence shows that nut intake is associated with reduced body weight and body fat. (Nishi et al. 2021)

There are a few mechanistic explanations…

1. Nuts have an optimal fatty acid profile, with a high concentration of monounsaturated and polyunsaturated fats and a low concentration of saturated fats.
2. We don’t absorb all the fat in nuts because a portion remains encapsulated within cell walls that are incompletely digested.
3. Nuts are also rich in protein and fibre, which make them more satiating.

A ton of research shows that eating nuts regularly can improve certain health markers.

Heart health: A daily serving of nuts (28g) was associated with a 19% reduced relative risk of cardiovascular disease. In a trial, a low dose of almonds (10g/day) before breakfast improved participants’ cholesterol levels. (Aune et al. * * 2016)

Longevity and lower risk of cancer: A small handful (28g) per day was associated with a reduced risk of total cancer and all-cause mortality. (Aune et al. 2016)

Improved memory: A trial found that older adults who ate 2 daily handfuls of mixed nuts every day (~60g) improved their performance in memory tests by 16%, compared to the control period without nuts. (Nijssen et al. 2023)

4. Go for ~1 handful of mixed nuts

In studies, doses ranged from 28 to 60 grams of nuts or about 1 to 2 handfuls per day.

Each nut has a special talent! For example, pecans contain the highest amount of phenolic acids, followed by walnuts and almonds. And isoflavones have only been reported in pistachios, while dihydrochalcones are present only in hazelnuts. So eating a variety is the best way to get the most nutrients and polyphenols.

5. They might be what your dish is missing…

Beyond an easy snack, nuts are valuable and versatile ingredients that can add the texture that elevates a meal. We enjoy adding nuts to…

1. Salads: Add toasted walnuts and hazelnuts to leafy greens or pecans to fruit salads.
2. Pasta sauces: Blend almonds into a pesto or add chopped walnuts to your bolognese.
3. Stir-fries: Toss in a handful of cashews or peanuts to add a satisfying crunch.
4. Roasted veggies: Scatter vegetable tray bakes with crumbled walnuts and fresh herbs.
5. Snacks with Greek yoghurt, dark chocolate, fruits, vegetables or cheese.

Recipes to try

• Golden Beetroot Bulgur Wheat Risotto with Spinach, Walnuts and Fresh Thyme
• Pumpkin, Kale, Leek and Cannellini Bean Lasagna with Sage and Walnut Crumb
• Lazy Chickpea Tagine
• Chunky Oat, Peanut Butter, Chocolate Chip, Fruit and Nut Cookies