You might have heard in the news or from a friend or family member that sugar is poison. Some new theories about nutrition have proposed this idea, and they have gained traction in the popular media. Unfortunately, they’ve gained more traction than the scientific evidence merits. Even though nutrition advice changes from time to time based on new research, there are some well-established facts that are not likely to change. And one of those facts is that sugar is NOT poison. It is, in fact, an important nutrient that plays a vital role in our health and functioning.

Three Reasons Sugar is Not Poison

1. It doesn’t fit the definition. Poison is, “a substance that through its chemical action usually kills, injures, or impairs an organism.” Sugar certainly does not kill, injure, or impair people. In fact, quite the opposite. We have built-in metabolic pathways to store and use sugar for critical functions.

   For example, glucose (a type of sugar) is the preferred source of energy for our entire nervous system, including the brain. It is also the only energy source that is efficient enough to fuel our muscles for high intensity exercise like sprinting or very heavy lifting. If you think of the ability to sprint extremely fast as critical to our survival in a primal sense, not only is sugar not poison, but it’s needed for survival!

2. It is part of natural, nutritious foods that are staples in our diet. Sugar is in one of the most natural foods known to mankind—breastmilk. The sweet taste of a mother’s milk or infant formula, which is from the sugar in these foods, is critical for the newborn baby to desire it, drink enough, and thrive and grow. Fruit, vegetables, dairy, and some grains are other foods that naturally contain sugars. If sugar were poison, why would all these nutritious, vital foods that we eat every day contain it? And why would humans have a natural inclination toward sweet taste that is necessary for thriving at birth?
3. Our bodies make it. Sugar is so important for our functioning that your body will make it if you don’t eat it. Your liver can generate sugar molecules from breaking down the glycerol backbone of fatty acids and from some types of protein. If sugar were toxic or poisonous, why would our bodies have a special ability to make it?

Too Much of a Good Thing?

Many nutrients have an optimal range of intake that promotes optimal functioning of the body. Vitamin A, for example, can give you a deficiency sickness that results in blindness if you don’t get enough. But it also can result in toxicity if you get too much, causing liver toxicity and skin problems. In nutrition, the saying, “too much of a good thing” applies often. It is possible to get too much or too little sugar for optimal functioning.

Too little isn’t really a concern in our current environment but getting too much is possible. The sugars that occur naturally in foods like fruit and vegetables do not add up to very much. However, added sugar, or the refined sugar that is added to foods to make them sweeter, can add up quickly. Foods like baked goods, candy, soft drinks, and sweet processed snacks can have a lot of added sugar in them.
There are two main reasons that too much added sugar might not be good for nutrition.

1. It gives us calories but no other nutrients. The body needs only a certain number of calories and eating more than that can cause weight gain. Eating a lot of foods with added sugars makes it easy to exceed caloric needs, especially because they taste good. At the same time, foods with a lot of added sugars give calories but not any other important nutrients the body needs. So, in a way they dilute the nutrient content of our food if they make up a lot of the diet.
2. Very high added sugar intake may be linked with Non-Alcoholic Fatty Liver Disease, Cardiovascular Disease, and Diabetes risk. This is where the “sugar is poison” idea comes from. However, the evidence for these links is fairly inconclusive, and this link is currently considered controversial in the field of nutrition.

The Bottom Line

Sugar is like any other nutrient: it is good to eat it in moderation. The Dietary Guidelines for Americans 2020-2025 recommend that 10% of calories or less come from added sugar. For a 2,000 calorie diet, that amounts to about 12 teaspoons of sugar per day. Of course, knowing what moderation is, and how to achieve that, is tricky! Especially when foods high in added sugar are everywhere. For some help, check out our free Dessert Cheat Sheet for all the details you need to know.