The Sweet Dangers of Sugar
Sugar has a bittersweet reputation when it comes to health. Sugar occurs naturally in all foods that contain carbohydrates, such as fruits and vegetables, grains, and dairy. Consuming whole foods that contain natural sugar is okay. Plant foods also have high amounts of water, fiber, protein, essential minerals, amino acids and antioxidants. Dairy foods also contain protein, enzymes, calcium and a well–balanced ratio of fat and water.
Since your body digests these foods slowly, the sugar in them offers a steady supply of energy to your cells. A high intake of fruits, vegetables, and whole grains also has been shown to reduce the risk of chronic diseases, such as diabetes, heart disease, and some cancers.
Consuming Too Much Sugar
However, problems occur when you consume too much added sugar—that is, sugar that food manufacturers add to products to increase flavor or extend food’s shelf life.
In the American diet, the top sources of added sugar are soft drinks, fruit drinks, flavored yogurts, cereals, cookies, cakes, candy, and most processed foods. But added sugar is also present in even the most unexpected products, like soups, bread, cured meats, marinara sauce, peanut butter and ketchup.
Many people rely on quick, processed foods for meals and snacks. Since these products often contain added sugar, it makes up a large proportion of their daily calorie intake. In the US, added sugars account for up to 17% of the total calorie intake of adults and up to 14% for children. Dietary guidelines suggest limiting calories from added sugar to less than 10% per day. The result is we consume way too much added sugar. Adult men take in an average of 24 teaspoons of added sugar per day, according to the National Cancer Institute. That’s equal to 384 calories.
Impact On Your Heart
In a study published in 2014 in JAMA Internal Medicine, Dr. Hu and his colleagues found an association between a high–sugar diet and a greater risk of dying from heart disease. Over the course of the 15–year study of over 30,000 people, those who consumed 17–21% of calories from added sugar had a 38% greater risk of dying from heart disease, compared to those consuming only 8% of calories from added sugar. Just one 20–ounce (591–ml) can of soda contains 65 grams of sugar, which equates to more than 12% of your daily calorie consumption, based on a 2,000–calorie diet. This means that just one sugary drink a day can already put you over the recommended daily limit for added sugar.
High–sugar diets have been associated with an increased risk of many chronic diseases, including heart disease, the number one cause of death worldwide. Evidence suggests that high–sugar diets can lead to obesity, inflammation and high triglyceride, blood sugar and blood pressure levels—all risk factors for heart disease. Additionally, consuming too much sugar, especially from sugar–sweetened drinks, has been linked to atherosclerosis, a disease characterized by fatty, artery–clogging deposits.
The effects of added sugar intake—higher blood pressure, inflammation, weight gain, diabetes, and fatty liver disease—are all linked to an increased risk for heart attack and stroke. Consuming too much added sugar can raise blood pressure and increase chronic inflammation, both of which are pathological pathways to heart disease.
Incidence of Type 2 Diabetes
The worldwide prevalence of diabetes has more than doubled over the past 30 years. Though there are a multitude of factors that affect the onset of any chronic medical condition, there is a clear link between excessive sugar consumption and diabetes risk. Obesity, which is often caused by consuming too much sugar, is considered the strongest risk factor for diabetes.
What’s more, prolonged high–sugar consumption drives resistance to insulin, a hormone produced by the pancreas that regulates blood sugar levels. Insulin resistance causes blood sugar levels to rise and strongly increases your risk of diabetes.
A population study comprising over 175 countries found that the risk of developing diabetes grew by 1.1% for every 150 calories of sugar, or about one can of soda, consumed per day. Other studies have also shown that people who drink sugar–sweetened beverages, including fruit juice, are more likely to develop diabetes.
Impact On Your Liver
The liver metabolizes sugar the same way as alcohol, and converts dietary carbohydrates to fat. A high intake of fructose has been consistently linked to an increased risk of fatty liver. Unlike glucose and other types of sugar, which are taken up by many cells throughout the body, fructose is almost exclusively broken down by the liver. In the liver, fructose is converted into energy or stored as glycogen.
However, the liver can only store so much glycogen before excess amounts are turned into fat. Large amounts of added sugar in the form of fructose overload your liver, leading to non–alcoholic fatty liver disease (NAFLD), a condition characterized by excessive fat buildup in the liver. A study in over 5,900 adults showed that people who drank sugar–sweetened beverages daily had a 56% higher risk of developing NAFLD, compared to people who did not.
Impact On Mental Health
While a healthy diet can help improve your mood, a diet high in added sugar and processed foods can increase your chances of developing depression. Consuming a lot of processed foods, including high–sugar products such as cakes and sugary drinks, has been associated with a higher risk of depression.
Researchers believe that blood sugar swings, neurotransmitter dysregulation and inflammation are all reasons for sugar’s detrimental impact on mental health. A study following 8,000 people for 22 years showed that men who consumed 67 grams or more of sugar per day were 23% more likely to develop depression than men who ate less than 40 grams per day. Another study in over 69,000 women demonstrated that those with the highest intakes of added sugars had a significantly greater risk of depression, compared to those with the lowest intakes.
Excessive Weight Gain & Obesity
Rates of obesity are rising worldwide and added sugar, especially from sugar–sweetened beverages, is thought to be the number one culprit. Sugar–sweetened drinks like sodas, juices and sweet teas are loaded with fructose, a type of simple sugar. Consuming fructose increases your hunger and desire for food more than glucose, the main type of sugar found in starchy (carbohydrate dense) foods. Additionally, excessive fructose consumption may cause resistance to leptin, an important hormone that regulates hunger and tells your body to stop eating.
Research has consistently shown that people who drink sugary beverages, such as soda and juice, weigh more than people who don’t. Also, drinking a lot of sugar–sweetened beverages is linked to an increased amount of visceral fat, a kind of deep belly fat associated with conditions like diabetes and heart disease.
In other words, sugary beverages don’t actually curb your hunger, they simply trick your body into turning off its appetite–control system because liquid calories are not as satisfying as calories from solid foods. This is why it is easier for people to add more calories to their regular diet when consuming sugary beverages. This is a dangerously fast way to gain weight.
Increased Chronic Inflammation
Diets high in sugar increase inflammation in your body. Science has proven that chronic, low–grade inflammation can turn into a silent killer that contributes to cardiovascular disease, cancer, type 2 diabetes and other conditions. Protecting yourself from the damage of chronic inflammation is one way to stay healthy.
Increased Cancer Risk
Eating excessive amounts of sugary foods and beverages leads to weight gain and even obesity, which significantly raises your risk of cancer. Furthermore, diets high in sugar increase inflammation and can cause insulin resistance, both of which increase cancer risk.
A study in over 430,000 people found that added sugar consumption was positively associated with an increased risk of esophageal cancer, pleural cancer and cancer of the small intestine. Another study showed that women who consumed sweet buns and cookies more than three times per week were 1.42 times more likely to develop endometrial cancer than women who consumed these foods less than 0.5 times per week.
Accelerates Cellular Aging
Telomeres are structures found at the end of chromosomes, which are molecules that hold part or all of your genetic information. Telomeres act as protective caps, preventing chromosomes from deteriorating or fusing together. As you grow older, telomeres naturally shorten, causing cells to age and malfunction. Although the shortening of telomeres is a natural part of aging, unhealthy lifestyle choices can speed up this process.
Consuming high amounts of sugar has been shown to accelerate telomere shortening, which increases cellular aging. A study in 5,309 adults showed that regularly drinking sugar–sweetened beverages was associated with shorter telomere length and premature cellular aging. In fact, each daily 20–ounce (591–ml) serving of sugar–sweetened soda equated to 4.6 additional years of aging, independent of other variables.
Accelerates Skin Aging
Wrinkles are a natural sign of aging. They appear eventually, regardless of your health. However, poor food choices can worsen the appearance of wrinkles and speed up the skin aging process. Advanced glycation end products (AGEs) are compounds formed by reactions between sugar and protein in your body. They are suspected to play a key role in skin aging. Consuming a diet high in refined (processed) carbohydrates and sugar leads to the production of AGEs, which can cause your skin to age prematurely.
AGEs damage collagen and elastin, which are proteins that help the skin stretch and keep its youthful appearance. When collagen and elastin become damaged, the skin loses its firmness and begins to sag. In one study, women who consumed more refined carbohydrates, including added sugars, had a more wrinkled appearance than women on a high–protein, lower– carbohydrate diet. The researchers concluded that a lower intake of carbohydrates was associated with better skin age appearance.
Linked to Incidence of Acne
A diet high in refined (processed) carbohydrates, including sugary foods and drinks, has been associated with a higher risk of developing acne. Foods with a high glycemic index, such as processed sweets, raise your blood sugar more rapidly than foods with a lower glycemic index. Sugary foods quickly spike blood sugar and insulin levels, causing increased androgen secretion, oil production and inflammation, all of which play a role in acne development.
Studies have shown that low–glycemic diets are associated with a reduced acne risk, while high–glycemic diets are linked to a greater risk. For example, a study in 2,300 teens demonstrated that those who frequently consumed added sugar had a 30% greater risk of developing acne. Also, many population studies have shown that rural communities that consume traditional, non–processed foods have almost non–existent rates of acne, compared to more urban, high–income areas. These findings support the hypothesis that diets high in processed, sugar–laden foods contribute to the development of acne.
Energy Highs and Lows
Foods high in added sugar quickly spike blood sugar and insulin levels, leading to increased energy. This rise in energy levels is fleeting. Products that are loaded with sugar but lacking in protein, fiber or fat lead to a brief energy boost that’s quickly followed by a sharp drop in blood sugar, often referred to as a crash.
Having constant blood sugar swings can lead to major fluctuations in energy levels. To avoid this energy–draining cycle, choose carbohydrate sources that are low in added sugar and rich in fiber. Pairing carbohydrates with protein or fat is another great way to keep your blood sugar and energy levels stable. For example, eating an apple along with a small handful of almonds is an excellent snack for prolonged, consistent energy levels.
Other Health Risks
Aside from the risks listed above, sugar can harm your body in countless other ways. Research shows that too much added sugar can also:
- Increase kidney disease risk: Having consistently high blood sugar levels can cause damage to the delicate blood vessels in your kidneys. This can lead to an increased risk of kidney disease.
- Negatively impact dental health: Eating too much sugar can cause cavities. Bacteria in your mouth feed on sugar and release acid byproducts, which cause tooth demineralization.
- Increase the risk of developing gout: Gout is an inflammatory condition characterized by pain in the joints. Added sugars raise uric acid levels in the blood, increasing the risk of developing or worsening gout.
- Accelerate cognitive decline: In the August, 2013 article in the New England Journal of Medicine, “Glucose Levels and Risk of Dementia,” researchers P.K. Crane et al found that high–sugar diets can lead to impaired memory and have been linked to an increased risk of dementia.
How Much Is Okay?
If 24 teaspoons of added sugar per day is too much, then what is the right amount? It’s hard to say, since sugar is not a required nutrient in your diet. The National Academy of Medicine (formerly known as the Institute of Medicine), which sets Recommended Dietary Allowances (RDAs), has not issued a formal number for sugar.
However, the American Heart Association (AHA) recommends limiting added sugar to 150 calories (about 9 teaspoons or 36 grams) per day for most men and 100 calories (about 6 teaspoons or 25 grams) per day for most women and children over 2. That is close to the amount in a 12–ounce can of soda. The average adult gets about 17 teaspoons of sugar each day—almost double the limit for men and triple the limit for women.
Where Added Sugar Comes From
| Rank | Food Group | Proportion of Average Intake |
|---|---|---|
| 1 | Soda/energy/sports drinks | 42.2% |
| 2 | Grain–based desserts | 11.9% |
| 3 | Fruit drinks | 8.5% |
| 4 | Dairy desserts | 5.5% |
| 5 | Candy | 5.0% |
| 6 | Ready–to–eat cereals | 2.9% |
| 7 | Sugars/honey | 4.1% |
| 8 | Tea | 3.8% |
| 9 | Yeast breads | 2.3% |
| 10 | Syrups/toppings | 1.4% |
Subtracting Added Sugar
Reading food labels is one of the best ways to monitor your intake of added sugar. When reading food labels, focus on the following two details:
- Look for the following names for added sugar and try to either avoid, or cut back on the amount or frequency of the foods where they are found.
- Brown sugar
- Corn sweetener
- Corn syrup
- Fruit juice concentrates
- High–fructose corn syrup
- Honey
- Invert sugar
- Malt sugar
- Molasses
- Syrup sugar molecules ending in “ose” (dextrose, fructose, glucose, lactose, maltose, sucrose)
- Total sugar, which includes added sugar, is often listed in grams. Note the number of grams of sugar per serving as well as the total number of servings. It might only say 5 grams of sugar per serving, but if the normal amount is three or four servings, you can easily consume 20 grams of sugar and thus a lot of added sugar.
Reduce (or Eliminate) Added Sugars
Added sugar should be kept to a minimum whenever possible, which is easy when you follow a healthy diet based on whole, unprocessed foods. It automatically decreases the amount of sugar in your diet with very little effort. If you need to cut added sugar from your diet, try some of these small changes as part of an overall healthy eating pattern:
- Eat plenty of fresh fruits and vegetables of all colors and types.
- Choose mostly nutrient–dense foods instead of empty calories.
- Keep a whole food mostly plant–based diet, avoiding processed foods.
- Replace sugary drinks with water and sugar–free options (options without sugar or any sweeteners of any kind, both natural and artificial, with or without calories).
- Sweeten plain yogurt with fresh or frozen berries instead of buying flavored, sugar–laden yogurt.
- Replace candy with a homemade trail mix of fruit, nuts and a few dark chocolate chips.
- Use olive oil and vinegar in place of sweet salad dressings like honey mustard.
- Choose marinades, nut butters, ketchup and marinara sauce with zero added sugars.
- Look for cereals, granolas and granola bars with under 4 grams of sugar per serving.
- Swap your morning cereal for a bowl of rolled oats topped with nut butter and fresh berries, or an omelet made with fresh greens.
- Instead of jelly, slice fresh bananas onto your peanut butter sandwich.
- Use natural nut butters in place of sweet spreads like Nutella.
- Avoid alcoholic beverages that are sweetened with soda, juice, honey, sugar or agave.
- Shop the perimeter of the grocery store, focusing on fresh, whole ingredients.
Also, keep track of sugar you add to your food or beverages. About half of added sugar comes from beverages, including coffee and tea. A study in the May 2017 Public Health found that about two–thirds of coffee drinkers and one–third of tea drinkers put sugar or sugary flavorings in their drinks. The researchers also noted that more than 60% of the calories in their beverages came from added sugar.
In addition, keeping a food diary is an excellent way of becoming more aware of the main sources of sugar in your diet. The best way to limit your added sugar intake is to prepare your own meals at home and avoid going out to eat too frequently to restaurants where you have no control of how the food is prepared. Limiting fast food and junk food to only once a week or even just once a month would go a long way in reducing your added sugar intake but also improving your overall health.
Yet, beware of finding yourself reaching for other foods to satisfy your sweet cravings. Refined starches, such as white bread and white rice, which can increase glucose levels, or comfort foods high in saturated fat and sodium, which can negatively impact heart health.
Sources:
11 Reasons Why Too Much Sugar Is Bad for You
https://www.healthline.com/nutrition/too-much-sugar
Written by Jillian Kubala, MS, RD on June 3, 2018
The sweet danger of sugar
https://www.health.harvard.edu/heart-health/the-sweet-danger-of-sugar
January 6, 2022
How Too Much Added Sugar Affects Your Health Infographic
https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/sugar/how-too-much-added-sugar-affects-your-health-infographic