A client of mine recently said, “I heard that fructose is converted to fat more than other forms of sugar. Does this mean I need to stop eating fruit if I want to maintain a lean physique? I really love my apples!”
Here's what I told her:
Keep eating your apples! Yes, there may be negative effects of eating too much fructose (same goes for glucose). However, the amount of fructose you need to eat to start seeing negative effects is extremely high. Research studies use solutions of pure fructose, rather than making their subjects eat fruit. Check out this more in-depth article that reviews some of the research.
From the article author, Michael Matthews:
"How exactly was this study conducted, though? Well, they had 16 guys consume a solution consisting of 3.5 grams of fructose per kilogram of weight every day. I weigh about 90 kilograms, so that would mean I would have to eat 315 grams of fructose per day. If I wanted to get that from bananas, I’d have to eat about 45. Or about 80 cups of strawberries. Or 800 cherries. Or 26 apples."
As you can see, negative effects of fructose require extremely high levels, which are usually found in artificially sweetened beverages (and lab studies!), not fruit.
Some more research bits and pieces for you to check out:
Check out this study, which made two important points:
1. "Fructose intake at normal population levels and patterns does not cause biochemical outcomes substantially different from other dietary sugars."
2. "Extreme experimental models that feature hyperdosing or significantly alter the usual dietary glucose-to-fructose ratio are not predictive of typical human outcomes or useful to public health policymakers."
"There's no reason to avoid fructose itself," says Madelyn Fernstrom, PhD, CNS, director of the Weight Management Center at the University of Pittsburgh Medical Center. If you're looking to lose weight -- or at least not gain any -- Fernstrom recommends that you limit your consumption of fructose-sweetened beverages and snack foods just as you would any simple carb. Of course, cutting back your total calorie intake wouldn't hurt either."
"In the recent study that was interpreted by the media and many readers as "fruit makes you fat," the subjects didn't even eat fruit! They were fed a huge dose of liquid fructose all at once -- 85 grams of carbs with a 75% fructose solution -- for a total of 64 grams of fructose."
"In humans, the liver can handle about 50 grams of fructose daily without stimulating any fat synthesis" <--- that's about 5 apples! Or 3.5 cups of blueberries!
Here's a meta-analysis of 41 experimental studies:
"Fructose is sometimes seen as a "dietary bad guy" in the battle against obesity, but a new study suggests it doesn't seem to cause weight gain when substituted for other carbs in diets providing similar calories."
"We're saying don't worry so much about the fructose. Concentrate on the energy. And certainly don't discount fruit."
...and there's much, much more research that all concludes the same thing.
So, based on the available research evidence, there's no fat-burning or body composition-related reason to completely cut fruit from the diet. In fact, I argue that would be unhealthy and unnecessary deprivation! It doesn't sound sexy, but moderation really is the name of the game. Anything in excess can cause negative outcomes, whether it's fructose, vitamins, or any other food ingredient.
So keep eatin' your apples!
Have questions? Wanna chat health and fitness? Just wanna say hi? Get in touch with me at any time.
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