11 Reasons Why Too Much Sugar Is Bad for You

How we reviewed this article: · Healthline

Key takeaways

Added sugar is fine in small amounts, but too much is linked to weight gain, acne, and a higher risk of type 2 diabetes and heart disease.

Dietary guidelines suggest keeping added sugar under 10% of daily calories, yet U.S. adults average about 17 teaspoons per day.

Cut added sugar by choosing whole, unprocessed foods, avoiding sugar-sweetened drinks, and checking labels on surprising sources like sauces and nut butters.

From marinara sauce to peanut butter, added sugar can be found in even the most unexpected products.

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 United States, the average adult consumes an estimated

17 teaspoons

of added sugar each day. That accounts for 14% of total calorie intake in adults following a 2,000-calorie diet.

Experts believe

that overconsumption of sugar is one of the many causes of obesity along with genetics, physical activity, and economic status.

That’s why dietary guidelines suggest limiting calories from added sugar to

less than 10%

per day.

Here are 11 reasons why eating too much sugar is bad for your health.

1. It can cause weight gain

Obesity rates are rising worldwide, and

evidence suggests

that added sugar — often from sugar-sweetened beverages — is a major contributor to obesity.

Consuming fructose increases your hunger and desire for food more than glucose, the main type of sugar found in starchy foods.

Additionally,

animal studies

show that excessive fructose consumption may cause resistance to

leptin

, an important hormone that regulates hunger and tells your body to stop eating.

In other words, sugary beverages don’t curb your hunger, making it easy to quickly consume a high number of liquid calories. This can lead to weight gain.

Research

shows

that consuming sugary beverages is associated with weight gain and increased risk of type 2 diabetes.

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

.

2. May increase your risk of 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.

A

study in over 25,877 adults

found that individuals who consumed more added sugar had a greater risk of developing heart disease and coronary complications compared to individuals who consumed less added sugar.

Not only does increased sugar intake increase cardiovascular risk, but it can also increase risk of stroke.

In the same study, more than eight servings per week of sugar-sweetened beverages were associated with increased stroke risk.

Just one 12-ounce (473-ml) can of soda contains

37 grams of sugar

and 155 calories, which equates to 8% of your daily calorie consumption, based on a 2,000-calorie diet.

This means that one sugary drink a day can bring you close to the

recommended daily limit

for added sugar.

3. Linked to acne

A diet high in refined carbs, including sugary foods and drinks, has been associated with a higher risk of

developing acne

.

Foods with a higher

glycemic index

, such as processed sweets, raise your blood sugar more rapidly than foods with a lower glycemic index.

Consuming sugary foods can cause a spike in blood sugar and

insulin

levels, leading to increased androgen secretion, oil production, and inflammation — all of which play a role in acne development.

Evidence

has shown that low-glycemic diets are associated with a reduced acne risk, while high-glycemic diets are linked to a higher acne risk.

For example, a

study of 24,452 participants

found that the consumption of fatty and sugary products, sugary beverages, and milk was associated with current acne in adults.

Additionally,

many population studies

have shown that rural communities that consume traditional, non-processed foods have much lower rates of acne compared to more urban, high-income areas where processed food is part of a standard diet.

However, this controlled study also showed that boys in the city had low rates of acne. Additional studies are needed.

These findings coincide with the theory that diets high in processed, sugar-laden foods contribute to the development of acne.

4. Increases your risk of type 2 diabetes

Diabetes is a leading cause of mortality and reduced life expectancy. Its prevalence has

more than doubled

over the past 30 years, and projections estimate its burden will continue to rise.

Excessive sugar consumption has been historically associated with an increased risk of diabetes.

While no study has proven that sugar consumption causes diabetes, there are strong connections.

Eating large amounts of sugar can indirectly raise diabetes risk by contributing to weight gain and increased body fat — both of which are risks for developing diabetes.

Obesity, which may be caused by excessive sugar consumption, 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.

Additionally,

research has found

that people who drink sugar-sweetened beverages are more likely to develop diabetes.

A study

including individuals who drank sugary beverages for over a 4-year period found that increased consumption of sugary beverages — including soft drinks and 100% fruit juice — is associated with a higher risk for type 2 diabetes.

5. May increase your risk of cancer

Eating excessive amounts of sugar may increase your risk of developing certain cancers.

First, a diet rich in sugary foods and beverages can lead to obesity, which significantly raises your risk of cancer.

Also, diets high in sugar increase inflammation in your body and may cause insulin resistance, both of which increase cancer risk.

A

systematic review

analyzing 37 prospective cohort studies found that in two of five studies on added sugar, a 60% – 95% increased cancer risk was observed with higher sugar intakes.

The same review found that in 8 of 15 studies on sugary foods and beverages, a 23% – 200% increased cancer risk was observed with greater sugary beverage consumption.

Other studies have found sugar intake to be linked to specific types of cancer.

A

study in over 22,720 men

spanning over 9 years found that increased sugar consumption from sugar-sweetened beverages was associated with a greater risk of prostate cancer.

A 2017 study

found that esophageal cancer was associated with increased consumption of

sucrose

, or table sugar, and sweetened desserts and beverages.

Research on the link between added sugar intake and cancer is ongoing, and more studies are needed to fully understand this complex relationship.

6. May increase your risk of depression

While a healthy diet can

help improve your mood

, a diet high in added sugar and processed foods may contribute to changes in mood and emotions. It may even increase your chances of developing depression.

High sugar consumption

has been linked

to cognitive impairments, memory problems, and emotional disorders like

anxiety

and

depression

.

Researchers

believe that chronic systemic inflammation, insulin resistance, and a disrupted dopaminergic reward signaling system — all of which can be caused by increased sugar consumption — may contribute to sugar’s detrimental impact on mental health.

A 2017 study

following 8,000 people 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

older 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.

7. May accelerate the skin aging process

Wrinkles are a natural sign of skin aging. They appear eventually, regardless of your health.

However, poor food choices can worsen 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 carbs

and sugar leads to the production of AGEs, which may cause your skin to age prematurely.

When collagen and elastin become damaged, the skin loses its firmness and begins to sag.

More research is needed to fully understand the connection between sugar and skin changes in humans.

8. Can increase 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, which causes cells to age and malfunction.

Although the shortening of telomeres is a natural part of aging, certain lifestyle choices can speed up the process.

Consuming high amounts of sugar

has been shown

to accelerate telomere shortening, which increases cellular aging.

A

pilot study

on 61 preschool-aged children found that increased consumption of sugar-sweetened beverages was associated with decreased telomere length, signifying cellular aging.

9. Drains your energy

Foods high in added sugar quickly spike blood sugar and insulin levels, leading to increased energy.

However, 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.

A

meta-analysis

examining sugar’s effect on mood found that carbohydrate consumption, especially sugar, lowers alertness within 60 minutes of consumption, and increases fatigue within 30 minutes after consumption.

To avoid this

energy-draining cycle

, choose carb sources that are low in added sugar and rich in fiber.

Pairing carbs 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.

10. Can lead to fatty liver

A high intake of fructose has been consistently linked to an increased risk of

fatty liver

.

Fructose is a common type of sugar, with one major source being

high fructose corn syrup (HFCS)

used to sweeten soda, candy, baked goods, cereals, and more.

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

nonalcoholic fatty liver disease (NAFLD)

, a condition characterized by excessive fat buildup in the liver.

An

animal study

found that feeding mice a high-fructose diet for long periods of time led to the deterioration of their intestinal barrier, liver inflammation, liver tumors, and signs of fatty livers compared to a control group.

The same study found that the same amount of fructose is more likely to lead to developing a fatty liver when consumed through beverages rather than food, and when consumed in a single setting compared to several doses spread over a longer amount of time.

A

2015 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.

11. 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:

Increase kidney disease risk: Fructose can increase serum concentrations of urate, leading to the development of kidney disease. Consistently high blood sugar levels can also damage the delicate blood vessels in your kidneys, increasing the 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: High-sugar diets can lead to impaired memory and have been linked to an increased risk of

dementia

, Alzheimer’s disease, and

stroke

.

Research on the impact of added sugar on health is ongoing, and new discoveries are constantly being made.

How to reduce your sugar intake

Excessive added sugar has many negative health effects.

Although consuming small amounts now and then is perfectly healthy, you should try to cut back on sugar whenever possible.

Fortunately, simply focusing on eating

whole, unprocessed foods

automatically decreases the amount of sugar in your diet.

Swap sodas, energy drinks, juices, and sweetened teas for water or unsweetened seltzer.

Drink your

coffee black

or use a

natural alternative

for a healthier option.

Sweeten

plain yogurt

with fresh or frozen

berries

instead of buying flavored, sugar-loaded yogurt.

Consume whole fruits instead of sugar-sweetened fruit smoothies.

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 butter

,

ketchup

, and marinara sauce with zero added sugars.

Look for

cereals

,

granola

, 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 butter 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.

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 healthy meals at home and avoid buying foods and drinks that are high in added sugar.

What is added sugar?

Added sugars are sugars that are added during the processing of foods, during preparation, or at the table.

For example, sucrose or dextrose added during food processing is an added sugar, as is honey used to sweeten tea at your kitchen table.

Fortunately, “added sugars” are listed separately on Nutrition Facts panels underneath the line for “total sugars,” making it easier to determine whether or not your food contains any added sugars.

What is considered a high-sugar food?

Foods that contain close to, or more than the recommended amounts, may be considered high in sugar.

Men should consume no more than

9 teaspoons

(36 grams or 150 calories) of added sugar per day.

Women should consume no more than

6 teaspoons

(25 grams or 100 calories).

Foods high in sugar include:

sweets, including candy, pie, cakes, and cookies

dairy desserts like ice cream and milkshakes

soda

fruit juice

sports drinks

low fat yogurt

condiments like

ketchup

, honey mustard, and BBQ sauce

many common

breakfast cereals

While some foods high in sugar may be obvious, many foods are surprisingly high in sugar.

Eating too much added sugar can have many negative health effects.

An excess of sweetened foods and beverages can lead to weight gain, blood sugar problems, and an increased risk of heart disease, among other dangerous conditions.

For these reasons, added sugar should be kept to a minimum whenever possible, which is easy when you follow a

nutrient-dense diet

based on whole foods.

If you need to cut added sugar from your diet, try some of the small changes listed above.

Before you know it, your sugar habit will be a thing of the past.