Is sugar bad for you? Can it really have a head-to-toe impact on the human body?

When we’re talking about added sugar, the answer is a resounding “yes.”

Although the sugar industry has actively fought to change public opinion about the health effects of sugar, we now know today that sugar impacts just about every organ system in the body.

And not in a good way.

Hopefully, the latest science on sugar will help inspire you to deal with sugar addiction.

Let’s take a look at the top ways added sugar destroys your body. (In a separate article, learn how much sugar per day is the right amount.)

Is Sugar Bad for You?

1. Ticker trouble

Most people blame dietary fat for heart disease, and while certain industrial, inflammatory fats like trans fats do cause heart attacks, sugar is the real culprit.

In fact, in 2016, researchers unearthed a huge sugar industry scandal, proving that the sugar lobby sponsored phony Harvard research in the 1960s.

Turns out the sugar lobby paid Harvard researchers to take the heat off of sugar’s health effects, instead turning the focus on naturally occurring fats’ supposed role in heart disease.

This faulty “research” concluded there was “no doubt” that the only dietary intervention required to prevent coronary heart disease was to eat less cholesterol and to eat polyunsaturated fat instead of saturated fat.

We now know this is not wholly true.

In 2014, researchers were able to scientifically show that ingesting too much added sugar could significantly increase your risk of dying from cardiovascular disease (CVD). In fact, people getting 17 percent to 21 percent of calories from added sugar faced a 38 percent higher risk of dying from cardiovascular disease compared to those who got just 8 percent of their calories from sugar.

The relative risk was more than double for those who consumed 21 percent or more of their calories from added sugar.

Lots of research has shown the link between sugar consumption and heart disease risk since.

For instance, a 2020 study revealed “that a diet with a greater proportion of sugar increased CVD risk via negative changes in metabolic profiles including body weight, waist circumference and lipid parameters, whereas LS produced the positive effects. A restriction of sugar intake to lower than 10% energy intake is vital to reduce CVD risk.”

Another study found that “added sugars drive coronary heart disease via insulin resistance and hyperinsulinaemia,” while a study from 2023 found all types of sugar actually heighten the risk of heart disease.

Today, most U.S. adults consume about 17 to 22 teaspoons of added sugars a day. That’s way more than what the American Heart Association (AHA) recommends.

AHA says:

• No more than six teaspoons or 100 calories a day of sugar for most women
• No more than nine teaspoons or 150 calories a day for most men

2. Fatty livers

Here’s another reason to reduce sugar intake. Non-alcoholic fatty liver disease is on the rise in the U.S., and guess what’s largely to blame? Sugar!

High fructose corn syrup hiding out in drinks and processed foods has been called a “weapon of mass destruction.” Non-alcoholic fatty liver (NAFLD) occurs when fat builds up in the liver.

According to a study conducted at the University of Sydney at Westmead Hospital in Australia, NAFLD is present in 17 percent to 33 percent of Americans (or 24 percent on average, according to research). This growing percentage parallels the frequency of obesity, insulin resistance, metabolic syndrome and type 2 diabetes, and many Americans with the disease don’t experience any symptoms.

Tuft University researchers discovered people who drink one sugar-sweetened beverage a day face a higher risk of non-alcoholic fatty liver disease compared to those who steer clear of beverages containing added sugars. (They also have an increased risk of dementia and stroke.)

Interestingly, the microbiome is at play, too.

You see, the microbiome serves as the interface between diet and the liver and modifies dietary effects. Scientists are actively investigating our guts’ role in non-alcoholic fatty liver disease.

What is clear? Drastically backing down on added sugar intake does seem to improve this disease to some extent.

3. Leaky gut and other metabolic diseases

Is sugar bad, particularly when it comes to the gut? You bet.

Knowing that the microorganisms that live in gut actually act similarly to a metabolic “organ,” researchers now believe sugar changes the gut microbiota in a way that increases intestinal permeability, aka leaky gut symptoms.

Eliminating excess added sugar is a key part of any effective leaky gut treatment plan. Added sugar feeds yeast and bad bacteria that can damage the intestinal wall, creating a leaky gut.

This means the chronic, low-grade inflammation that sugar triggers can lead to the transfer of substances from the gut into the bloodstream. This can trigger obesity and other chronic, metabolic diseases.

On a similar note, a December 2014 study found sugar-sweetened soda drinks may influence the development of metabolic diseases. Researchers determined soda drinkers had shorter telomeres, a sign of decreased longevity, and accelerated cell aging.

4. Diabetes-prone body

A 2013 study published in the journal PLOS ONE found for every 150 calories of sugar a person consumes a day (about the equivalent of a can of soda), that person increases her risk of type 2 diabetes by 1.1 percent. This increased risk held true even considering researchers adjusted for the other types of foods people eat (including meat, oils, cereals, high-fiber foods, etc.).

Researchers also found the impact of sugar on diabetes held true regardless of a sedentary lifestyle and alcohol use.

This is no surprise considering sugar has a direct impact on diabetes.

5. Number of cancers

Does sugar impact cancer risk? When the National Institutes of Health set out to investigate sugar’s link to 24 different cancers, it didn’t find tons of published research, noting more is needed, but its researchers were able to find some associations between different types of sugar and certain cancers.

For instance, added sugars increase the risk of esophageal cancer, while added fructose (think high fructose corn syrup dangers) appeared to increase the risk of cancer in the small intestine.

Other research hints at a connection between high intake of added sugars and colon cancer. This higher risk remained even after adjusting for other colon cancer risk facts like being overweight or obese or having diabetes.

Dietary sugar could also increase the risk of breast cancer tumors and metastasis to the lungs.

The University of Texas MD Anderson Cancer Center published a 2016 study finding high amounts of dietary sugar in the typical Western diet seem to affect an enzymatic signaling pathway known as 12-LOX (12-lipoxygenase) in a way that increases breast cancer risk.

“We found that sucrose intake in mice comparable to levels of Western diets led to increased tumor growth and metastasis, when compared to a non-sugar starch diet … Prior research has examined the role of sugar, especially glucose, and energy-based metabolic pathways in cancer development. However, the inflammatory cascade may be an alternative route of studying sugar-driven carcinogenesis that warrants further study,” said Peiying Yang, Ph.D., assistant professor of palliative, rehabilitation and integrative Medicine.

The researchers pinpointed fructose, a component of table sugar and high fructose corn syrup, as the responsible sugar facilitating lung metastasis in the breast tumors studies. Previous epidemiological studies have shown that dietary sugar intake has an impact on breast cancer development, with inflammation thought to play a role.

In an animal study, 30 percent of mice on the starch-control diet exhibited tumors.

The sucrose-enriched diets? Fifty percent to 58 percent had mammary tumors. (Sucrose is the main component of table sugar).

The breast cancer was more likely to spread to the lungs in mice fed the sucrose- or fructose-enriched diet compared to the starch-control diet.

Sugar Ingredients to Avoid

Added sugars can fall under all sorts of different names on ingredient labels.

One rule of thumb to find these hidden sugars is that any ingredient ending in “ose” is a type of sugar.

Don’t be fooled by more natural-sounding names either. Sweeteners like cane juice, beet sugar, fruit juice, rice syrup and molasses are still types of sugar.

Check out their placement in the ingredients list, too. The higher up an ingredient is on the list, the more of it is included in a product.

Other names for added sugar include:

  • Anhydrous dextrose
  • Brown sugar
  • Confectioner’s powdered sugar
  • Corn syrup
  • Corn syrup solids
  • Dextrose
  • Fructose
  • High fructose corn syrup (HFCS)
  • Invert sugar
  • Lactose
  • Malt syrup
  • Maltose
  • Molasses
  • Nectars (for example, peach or pear nectar)
  • Pancake syrup
  • Raw sugar
  • Sucrose
  • Sugar
  • White granulated sugar

Final Thoughts

  • Is sugar bad for you? Yes, indeed. Added sugar can significantly increase your risk of early death.
  • Sugar impacts brain function, can cause non-alcoholic fatty liver disease and increases your risk of heart disease.
  • Added sugars appear to increase the risk of breast cancer and metastasis to the lungs.
  • There are dozens of names for added sugar on ingredient labels.
  • Simply dialing back on processed foods and drinks can lower your sugar intake. It’s also a great weight loss tip for women.
  • If you do use sugar, use less processed forms, but use them sparingly. Alternatively, I recommend using green stevia for sweetening purposes. Allulose is another alternative worth exploring.
  • Getting enough high-quality protein, fiber and fermented foods can help you lose your sugar cravings over time.

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