According to a study published in 2013, nearly one in five US deaths is now associated with obesity. Obesity is indeed a marker for chronic and potentially deadly disease, but the underlying problem that links obesity to so many other serious health issues—including heart disease—is metabolic dysfunction.

Mounting evidence clearly shows that added sugars, and processed fructose in particular, is a primary driver of metabolic dysfunction.

Refined fructose is actually broken down very much like alcohol, damaging your liver and causing mitochondrial and metabolic dysfunction in the same way as ethanol and other toxins.

It also causes more severe metabolic dysfunction because it’s more readily metabolized into fat than any other sugar. The fact that refined fructose is far more harmful to your health than other sugars was recently highlighted in a meta-review published in the Mayo Clinic Proceedings.1

The average American consumes one-third of a pound of sugar per day, half of which is processed fructose. Other statistics found in Dr. Richard Johnson’s book, The Sugar Fix,² suggest about 50 percent of Americans consume as much as half a pound, more than 225 grams, per day!

The majority of all this sugar is hidden in processed foods and beverages, so to address obesity and related health issues like diabetes and heart disease, ridding your diet of processed fare is key for success.

WHO Urges Slashing Sugar Consumption to Protect Health

To lower your risk of obesity and tooth decay, the World Health Organization (WHO) recommends dramatically reducing your sugar consumption, limiting added sugar to 10 percent of daily calories or less.³ This equates to about 12 teaspoons or 50 grams of sugar for most adults.

To prevent chronic disease such as diabetes, heart disease, and cancer, the organization suggests limiting your sugar consumption to a maximum of five percent of your daily calories.

The latter five percent limit is right in line with my own standard recommendation for healthy people, which calls for keeping your total fructose consumption below 25 grams per day, or about five teaspoons.

However, if you already have signs of insulin resistance, such as hypertension, obesity, or heart disease, I believe you’d be wise to limit your total fructose consumption even further—down to 15 grams or less until your weight and other health conditions have normalized.

Three recent studies that have linked excessive sugar consumption to chronic disease include the following:

       • According to the meta-review⁴ mentioned earlier, the preponderance of research clearly shows that once you reach 18 percent of your daily calories from added sugar, there’s a two-fold increase in metabolic harm that promotes prediabetes and diabetes
       • Most recently, a study published in the Journal of the American Medical Association (JAMA)⁵ concluded that “most US adults consume more added sugar than is recommended for a healthy diet,” and that there’s “a significant relationship between added sugar consumption and increased risk for cardiovascular disease mortality.”

        The 15-year long study, which included data for 31,000 Americans, found that those who consumed 25 percent or more of their daily calories as sugar were more than twice as likely to die from heart disease as those who got less than 10 percent of their calories from sugar.

        On the whole, the odds of dying from heart disease rose in tandem with the percentage of added sugar in the diet regardless of the age, sex, physical activity level, and body-mass index.
       • A 2014 study⁶ came to very similar results. Here, those who consumed the most sugar — about 25 percent of their daily calories — were twice as likely to die from heart disease as those who limited their sugar intake to seven percent of their total calories.