Fruit is widely recommended by health organizations despite containing sugars, including fructose. Recently, fructose has been shown to increase uric acid levels in the blood which can lead to hyperuricemia, gout, and kidney disease. Should we be worried about the effect of fruit on uric acid? Can eating fruit cause gout? Let’s take a look at the most up to date information.
What’s fructose then?
Fructose is a common fruit sugar, you probably eat it all the time without even knowing. It’s a key component of sucrose, or table sugar, where molecules of fructose are bonded to glucose. Fructose is found in fruits, honey, flowers, and root vegetables. Fructose, either alone or as a part of sucrose, is commonly added to foods for taste enhancement.
Like other sugars, excessive consumption of fructose contributes to insulin resistance, obesity, and metabolic syndrome. Recently, fructose consumption has fallen under scrutiny due to its harmful effects on the body. Fructose metabolism in the liver leads to the production of uric acid, a metabolic waste product that is normally filtered out of the bloodstream by the kidneys.
Uric Acid causes gout and kidney disease at high levels
Too much uric acid in the blood can lead to hyperuricemia, a condition that causes gout and can lead to kidney disease. This is a concerning issue due to the recent increase in added sugars to food items, including high-fructose corn syrup. Despite this, fruit consumption is always recommended by health organizations as a low energy-dense food rich in micronutrients.
This may be seen as a contradiction in nutritional advice as fructose from fruits is promoted and fructose from other foods is to be limited.
Some nutritionists have questioned whether fructose from fruit has the same effects on increasing uric acid as does fructose added to other food items.
To answer this question, a new study published in the American Journal of Clinical Nutrition compared the effects of fructose from whole fruit and fruit juice with a beverage with added fructose on uric acid concentration.
Does the Source of Fructose Make a Difference?
In this study, 73 patients were randomly assigned to a group to either ingest small or large servings of apples, small or large servings of apple juice, or a sugar-sweetened beverage.
The researchers collected blood samples of these individuals at baseline, 30 minutes after consumption, and 60 minutes after consumption.
Fructose from Fruit Raised Uric Acid Levels
The researchers found that plasma uric acid concentrations increased after the intake of all fructose-containing food items, regardless of fructose source.
This shows that the body’s responses to fructose are similar regardless of whether it is consumed from natural or artificial sources.
These results may have important implications for health nutritionists.
It is possible that consuming fruits and fructose-sweetened foods throughout the day may result in a chronic increase in uric acid.
However, it is not yet known whether small increases in uric acid, such as those which occur following fruit consumption, contribute to disease risk, or how long uric acid stays in the blood following fructose consumption.
Long-term studies are required to assess how small and transient changes in plasma uric acid affect health.
Does eating fruit cause gout?
As with most things in life, moderation is key. If you are in good health and eating a balanced diet, a slice of melon or a bowl of strawberries won’t do you any harm. If you are concerned about your uric acid levels, on the other hand, you might want to be more conservative about your fructose intake.
Written by Neeti Vashi, BSc
Reference: White, S. J. (2016). The effects of apples and apple juice on acute plasma uric acid production and satiety: a randomised controlled trial (Doctoral dissertation, University of Otago).
