Let’s look into the science behind the suggestion that nuts can help you to get or stay trim.
Are Nuts Healthy?
Firstly, nuts are extremely healthy and are good sources of fat, fibre and protein. They also pack a number of important vitamins and minerals, including magnesium and vitamin E.
Nuts are full of nutrients and antioxidants and their consumption has been linked to helping with a number of different diseases, including coronary heart disease, type 2 diabetes, some types of cancer and numerous other chronic conditions.
For the calorie counters amongst us, nuts do have a high calorific value, this is because a large part of a nut is fat, which is a concentrated form of energy. As a general rule, a gram of fat contains just over twice as many calories as the same amount of carbs or protein. The good news is that most nuts contain ‘good’, mainly monounsaturated fat along with some polyunsaturated fats including omega-6 and omega-3.
While nuts sound like the original superfood, most health benefits are attributed to nuts that have been minimally processed and contain no added ingredients. Processed nut products, such as peanut butter, often contain high amounts of salt, oil or added sugar. As a result, it’s best to buy nuts with nothing else added.
Can They Really Contribute to Weight Loss?
With nuts being high in fat and calories, it’s natural to think that increasing your intake will lead to weight gain but new scientific research tend to suggest otherwise.
Researchers from the US believe that a simple intervention could assist weight loss and help slow down the advent of ‘middle aged spread’, the progressive weight gain that often accompanies ageing.
A recent long-term study conducted by Harvard University and Harvard Medical School analysed information on weight, diet and physical activity in a large group of people comprising 27,521 male and 117,364 female health professionals. Participants in the study were asked to record their weight, exercise activities and how often they had eaten a serving of nuts.
The study concluded that increasing consumption of any type of nut was linked to less long-term weight gain and a lower risk of becoming obese. The researchers point out that while the study was observational and not intended to determine cause, some clear patterns did emerge.
- Replacing an unhealthy snack with just half a daily serving of nuts was linked both to less weight gain and a lower risk of obesity.
- Increasing consumption of any type of nut was linked to less long-term weight gain and a lower risk of becoming obese.
- Increasing nut consumption by half a serving a day was associated with a lower risk of putting on two or more kilos over any four-year period.
- Substituting snacks such as chocolates, pastries, pies and donuts with half a serving of nuts was associated with preventing weight gain of between 0.41 and 0.70kg in any four-year period.
- A daily half serving increase of walnuts was linked to a 15 per cent lower risk of obesity.
The findings remained after taking account of changes in diet and lifestyle, such as exercise and alcohol intake.
While the study didn’t attempt to establish the underlying reasons, some contributing factors were suggested, including:
- That chewing nuts takes more effort than eating fast food, while the high fibre content can make people feel full for longer.
- Nut fibre binds well to fat in the gut, meaning more fat and therefore more calories are excreted.
As with any diet, it’s important that you adopt a balanced approach and there’s evidence to suggest that the composition and quality of diet as well as calorie counting plays an important role in achieving and maintaining weight loss.
IMPORTANT: A number of people are allergic to nuts and eating — or even just being exposed to — a small amount can trigger an allergic reaction. Nuts are one of the most common triggers for anaphylaxis — a severe reaction that can be life threatening.
If you think someone is experiencing anaphylaxis, call triple zero (000) for an ambulance and start anaphylaxis first aid.
Further Reading:
Changes in nut consumption influence long-term weight change in US men and women https://nutrition.bmj.com/content/early/2019/08/27/bmjnph-2019-000034
Why nutritionists are crazy about nuts
https://www.health.harvard.edu/nutrition/why-nutritionists-are-crazy-about-nuts
Nuts – A healthy treat
https://www.health.harvard.edu/healthbeat/nuts-a-healthy-treat
Australian Dietary Guidelines
https://www.eatforhealth.gov.au/sites/default/files/files/the_guidelines/n55_australian_dietary_guidelines.pdf