Is it better to consume sugar or sweeteners?

We need to go beyond sugar vs. sweetener. We need to understand what each thing is. Sugar — what we normally know as table sugar, which is the most refined — is a non-essential food. It is rather a fruitive type of complementary food — those that produce pleasure but have no nutritional value — which is part of culinary preparations or as an ingredient in other mixtures.

Sucrose, found in table sugar, is a simple carbohydrate, composed of two monosaccharides: glucose and fructose, and is therefore rapidly absorbed. Its only function is energy, it does not provide anything else. One gram of sugar provides four kilocalories. As it is rapidly absorbed, it immediately passes into the blood, where it increases glucose levels: this has repercussions for health, especially in diabetics. The effects of sugar on the incidence of tooth decay are also well documented.

Sugar is used primarily to sweeten food, and sweeten life. It is not bad — it is not a poison — it all depends on the dose in which you take it. You can consume sugar, of course. The problem is that we do not only consume table sugar, it is also hidden in many foods, in sauces such as ketchup, pastries, soft drinks, sweetened dairy products, sweets, candies, etc., and also in many other ultra-processed foods.

Because of its calorific value, if you consume too much of it, you can put on weight. Most of the time, sugar is dispensed with for this reason. And we replace it with sweeteners — natural or synthetic — because we have become very accustomed to sweet flavours, which are more palatable. The European Union has authorized 19 sweeteners. Among them, there are natural ones such as xylitol, which when consumed in excess has a laxative effect, causing gastrointestinal discomfort and diarrhea; they are mainly found in sweets and sugar-free chewing gum.

However, all authorized sweeteners have been approved because they do not pose any health risks, unless they are consumed in excessive quantities. This can happen if you eat a lot of foods that contain sweeteners, although it is unlikely. According to EU regulations, you should not consume more than 2 mg per kilo of weight. To give you an idea, that would be 25 sachets of saccharin.

Most sweeteners are calorie-free, except for polyalcohols, such as xylitol in sweets, which have 60% fewer calories than sugar. What no sweetener has is any nutritional value: its only purpose is to enhance sweetness. The latest recommendations from the WHO call for reducing the consumption of synthetic sweeteners and using more natural ones. The reason for this is that they are being used to lose weight and it has been proven that this does not work. In strategies to lose weight or reduce caloric intake, what is influential is the dietary pattern, everything that is consumed. There’s no point in sticking to sweeteners if you then eat industrial pastries that are high in fat content and don’t exercise. It is more important to lead a healthy lifestyle.

The doses authorised by the EU do not pose any health risks, which is why it is better for a person who, for example, has tooth decay to use sweeteners rather than sugar. A diabetic who cannot take sugar must resort to sweeteners, preferably calorie-free ones. But it is also important to know that consuming sweeteners does not reduce the risk of cardiovascular disease or obesity. And it is also very important to note that each situation requires individualized guidance.

María José Castro Alija is a physician specializing in clinical nutrition, a researcher and professor at the faculty of nursing at the University of Valladolid, and a member of the VIMAS+ research group (Multidisciplinary Assessment and Intervention in Health Care and Sustainable Lifestyles).

This article is part of an initiative sponsored by the L’Oréal-Unesco ‘For Women in Science’ program and Bristol Myers Squibb to answer readers’ questions about science and technology. This question was sent in by Paula García.

The advice in this article is general in nature and is not a substitute for medical advice. If you have questions about your specific problem, please contact your health care professional.

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