The human sweet tooth was an epic evolutionary advantage and added sugar is becoming a serious problem.

While it causes significant health issues in modern society, far back in human history, craving sugar was a matter of survival. Sugar is a fast source of energy, and it is easily converted into fat for storage. The more fat stores you had, the more likely you would survive in lean times. 

The brain also prefers sugar as its primary source of energy. In many ways, our bodies evolved to keep our brains alive, so whatever the brain wants, it gets. 

All of this means that if you are like most of us, your body craves sugary foods. However, what started as a clever evolutionary adaptation is now an evolutionary mismatch. And it’s causing us problems.

The Human History of Sugar

Our modern environment has rapidly changed from the environment humans evolved in. 

The process of evolution cannot predict the future. This means humans evolved over a long period of time to be ideally suited to the naturally occurring environment on earth at the time.

It is only in the last 2000 years or so, and especially in the last few centuries that humans drastically altered the natural environment. We have changed how we live, what we eat, how we move, and how we interact with the world around us. From an evolutionary perspective, these changes have happened so quickly that the process of adaptation has yet to catch up.

So, what does this mean for sugar?

An Evolutionary Mismatch

Added Sugar

If you were an early, prehistoric human that didn’t like sweet-tasting foods, you would probably be dead. 

The sweeter a food is, the more sugar it contains. More sugar equals more energy. So, for early humans, the drive to find and consume sweet foods was all about giving themselves the best chance at survival. 

Seeking out and consuming sweet-tasting foods gave an immediate benefit in the form of quick energy, plus a long-term advantage in the form of storage for a later date. An early human who turned their nose up at sugary foods like fruit, honey, and carrots, probably died in the first scarce winter.

So, humans who loved sugary foods are the ones who won the evolutionary lottery. And we are their ancestors with the same DNA handed down through generations. However, most of us no longer struggle with the same problem of fluctuating food availability. 

The natural selection that brought us sugar cravings now works to our disadvantage. It’s a perfect example of an evolutionary mismatch. What was a survival mechanism in the past no longer serves us in our current, considerably changed environment. 

The abundance of sugar available combined with our brain’s natural sweet tooth is a recipe for disaster. While there is hope for humans far in the future to develop adaptations to this mismatch, today’s this means we have to battle our own instincts in order to be healthy.

Sugar and Health

The word sugar likely brings up images of cookies, candies, soda, and ice cream. You know, the good stuff. 

These foods are full of added sugar, meaning instead of naturally occurring sugar like those found in fruit, sweet treats are made solely as vehicles for sugar. As delicious as they may be, these foods offer little nutritional benefit and provide empty calories, fat, and lots of unnecessary sugar. 

What our prehistoric ancestors considered sweet is nothing compared to the refined sugar and high fructose corn syrup that are staples of a modern diet. At no other time has sugar been so cheap and easy to come by. In fact, the challenge is how to avoid it.

The Effect of Sugar on the Body

There are numerous negative consequences of eating a diet high in added sugar.

  • When you eat a dose of sugary food, your brain receives a surge of the feel-good neurotransmitter dopamine. The more often you eat added sugar, the more your brain will crave the rush of pleasure. Sugars’ impact on the brain over time is why our high sugar diets are often compared to an addiction. (1)
  • High levels of sugar in the bloodstream signal the pancreas to secrete large amounts of insulin. When the body is regularly exposed to high levels of insulin, it can damage the blood vessels, promote obesity, cause hypertension and decrease lifespan. (2)
  • Sugary foods make you more likely to experience cavities and tooth decay. (3)
  • A diet high in added sugar puts you at an increased risk of becoming overweight or obese. (4)
  • Added sugars replace nutrient-dense food in the diet, leading to a state of “internal starvation” where the body is deprived of an adequate amount of critical nutrients even while receiving excess calories. (5)

Diets high in added sugar dramatically increase your risk of heart disease, type 2 diabetes, cancer, and metabolic syndrome. (6)

How Much Sugar Can We Eat?

The simplest answer to this question is to try to eat as little added sugar as possible.

On average, Americans consume upwards of 17 teaspoons of added sugar per day. This is the equivalent of about two cans of soda.

In contrast, the World Health Organization recommends consuming no more than 6 teaspoons (or 24 grams) of added sugar per day for maximum health. (7) When you consider that just 1 tablespoon of ketchup contains a whole teaspoon of added sugar, it’s easy to see how this can be a challenge.

To decrease added sugars, you have to do more than avoid sugary treats, though that is an ideal starting point. There are also hidden sources of sugar in many common foods. Unfortunately, added sugar is such a standard part of the American diet that we often don’t even know it’s there.

Limiting Added Sugar

Added Sugar

In good news, added sugars are only found in foods that have been processed. Whole, unprocessed foods are naturally free of added sugars.

Sadly, we humans are the architects of our own struggle, as our desire for tasty, sugary foods has led us to add sugar wherever we can.

To conquer our inborn instinct, we have to get smart about sugar. Here are ways to limit added sugar in your diet.

Read Labels

In 2016, the FDA began requiring all food labels to list the amount of “added sugar” instead of just the amount of total sugar. Naturally occurring carbohydrates and sugar in foods are of much less concern than all the extra added in processing. Keeping the goal of 24 grams in mind, read labels and consider if the food is worth the added sugar.

Skip Dessert

This recommendation will be challenging for some people, but long-term success at limiting added sugar intake requires new habits. Sugary treats should be for special occasions, not an everyday occurrence. If skipping a treat is a big departure from your norm, then start small. For example, instead of going cold turkey, could you go without a treat on just one or two days a week? As your willpower increases, so will your days without dessert.

Eat Fruit

Opt for a piece of fruit if you have an intense sugar craving. In addition to the naturally occurring sugar, you will also get the benefit of healthy fiber, vitamins, and minerals.


When you crave sugar, pause to assess what might be causing the craving. A desire for sweets could signal that your brain is tired and wants a quick pick-me-up. However, sugar is not the only way to get it. For example, go for a brisk walk, lie down and close your eyes for a few minutes, or drink some water to rehydrate. It’s also possible your craving is about getting the feel-good shot of dopamine. But, there are other ways to meet that need. Spend time with a loved one, listen to music or do some deep breathing. Sugar is a poor substitute for what we really need.

Plant-based Diet

Fill up on healthy foods. Eating a wholesome, plant-based diet that meets your nutritional needs will reduce your desire for sugar. Let a quality diet crowd out the junk food.

Keep in mind that the goal is to limit added sugar, not necessarily naturally occurring sugars found in fruits, whole grains, and dairy. While it is certainly possible to overeat these types of foods, for most people, added sugar is the real culprit.

There Are Better Things in Life than Sugar

Added Sugar

While a slice of cake or a cookie may be pleasurable at the moment, their power to make us happy is limited. Eating sugar usually leaves us wanting more sugar. The craving just keeps coming back.

Seeking to satisfy our sweet tooth is an endless task that has no lasting reward. Our bodies do not need the energy from added sugar, even if our evolutionary instincts tell us otherwise.

What we truly need for survival in the modern age is better sleep, healthier food, more peace and connection, and less hustle and stress. Sugar does not nourish us or contribute to our health. Life has better things to offer. Listen to those cravings instead.


  1. Accessed 6/10/21
  2. Accessed 6/10/21
  3. Accessed 6/10/21
  4. Accessed 6/10/21
  5. Accessed 6/10/21
  6. Accessed 6/10/21
  7. Accessed 6/10/21