Carbohydrates: What's the magic number?


There’s a constant debate when it comes to carbohydrates. How much is too much? Is there such a thing as too little? A recent study published in The Lancet might have gotten us one step closer to the answer.


What the research says

To sum up the study, the researchers looked at carbohydrate intake and risk of all-cause mortality (any cause of death). They found that low-carbohydrate or high-carbohydrate diets increased the risk of all-cause mortality. While people sitting nicely in the middle, with a carbohydrate intake making up ~50-55% of their diet, were least at risk.


Digging deeper

The amount of carbohydrates you eat isn’t the only thing to consider, your protein and fat sources also matter. For instance, if you choose to limit your carbohydrate intake, you should opt for more plant-based protein and fat sources. If you substitute carbohydrates with more animal-based protein and fat sources it seems to increase your risk of all-cause mortality.

This study also highlights the problem with some low-carbohydrate diets. When carbohydrates are reduced, nutrient-packed foods like fruits, vegetables, and whole-grains are also reduced. This means you’re getting less fibre, vitamins, minerals, and antioxidants — which are all essential to your long-term health.

Also, keep in mind that it's the "good" types of carbohydrates that lower your risk of all-cause mortality. So opt for things like fruits, vegetables, peas, legumes, and whole-grains, like brown rice, oats, and quinoa. If your diet is full of refined carbohydrates, like cakes, white pasta, and white bread, you’re not doing yourself any favours.



Every study has its limitations. The researchers pointed out that this study relied on food questionnaires — which don’t tend to be 100% accurate. However, the findings are also supported by other large-scale studies like the Nurses’ Health Study and Health Professionals Follow-Up Study which is a good sign of the quality of evidence.


In a nutshell

Everything in moderation! For most of the population, opting for a moderate intake of healthy carbohydrates, like whole-grains, fruits, and vegetables, with lots of plant sources of protein and fats, like olive oil, legumes, and nuts might be the key to long-term health.

If you do decide to follow a low-carbohydrate diet, substituting carbohydrates with more plant-based sources of protein and fat instead of animal-based sources might help lower your risk of all-cause mortality.



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