Fructose

Food Sources

Foods that contain Fructose.

• High-fructose corn syrup

  Sugar consumption really took off after the Farm Bill of 1973 led to a glut of corn available for processing as high-fructose corn syrup.

  Source: Nutrition, Food and Diet in Ageing and Longevity

• Soft drinks

  We are almost literally swimming in a sea of fructose, especially in the form of soft drinks; Zelman's patient drank as many as twenty bottles of Coca-Cola in a single day

  Source: Outlive

• Fruit juice

  If we are drinking quarts of apple juice, it's a different story; liquid fructose overwhelms the gut and liver

  Source: Outlive

• Fruit (whole)

  Fructose does not pose a problem when consumed in the form of actual fruit; fructose enters our system relatively slowly, mixed with fiber and water; Long ago, when we consumed fructose mainly in the form of fruit and honey

  Source: Outlive

• Bottled Salad Dressing

  Fructose hidden in more innocent-seeming foods like bottled salad dressing and yogurt cups

  Source: Outlive

• Sweetened Yogurt Cups

  Fructose hidden in more innocent-seeming foods like bottled salad dressing and yogurt cups

  Source: Outlive

• Honey

  Long ago, when we consumed fructose mainly in the form of fruit and honey

  Source: Outlive

• Soda

  Sugar-sweetened sodas are a major source of fructose in the Standard American Diet

  Source: Outlive

Biological Mechanisms

How Fructose works at a cellular level.

• PromotesPromotes inflammation

  Excess fructose causes mitochondrial dysfunction, inflammation, and oxidative stress due to ATP depletion

• PromotesDrives excess fat production in liver

  If greater than about 10% of daily caloric intake is composed of sucrose, the fructose overloads the liver with a large carbon load. Fat synthesis pathways are upregulated leading to excess fat production, dyslipidemia, and eventually insulin resistance.

• PromotesFructose Converted to Fat in Liver

  Fructose is metabolized differently from glucose; large quantities overwhelm the gut and get shunted to the liver where many of those calories end up as fat

• PromotesFructose Produces Uric Acid

  When we metabolize fructose it produces large amounts of uric acid; humans lack the uricase enzyme to clear it efficiently

• PromotesFructose Tricks Cells into Feeling Hungry

  Fructose basically tricks our metabolism into thinking that we are depleting energy and need to take in still more food and store more energy as fat

• PromotesDisrupts Metabolism and Energy Balance

  Now fructose is vastly overabundant in our diet, too much of it in liquid form, which disrupts our metabolism and our overall energy balance

• PromotesMetabolized Preferentially in the Liver

  Like fructose, alcohol is preferentially metabolized in the liver

• PromotesDepletes Cellular Energy (ATP)

  Fructose does not put the brakes on ATP spending the way glucose does (Johnson et al. 2017); Rick Johnson's team realized fructose was having effects beyond calories

• PromotesPromotes Fat Storage

  Fructose metabolism promotes fat storage in the liver and drives metabolic dysfunction

Sources

• Nutrition, Food and Diet in Ageing and Longevity
• Outlive