Universal Nutrition Forum

Why fructose is a problem for dieters:

If you have a lot of fructose in your diet, it only has one place to go: your liver. If your liver glycogen levels are full, which is the case all times of the day except before you eat breakfast, then that fructose is turned into fat!

Since your liver doesn't want to store this new fat, it ships it to other parts of your body; places you don't want it, like your abdomen or lower back.

Do you now see why too much fructose in your diet can be one of the biggest reasons you can't shrink those last few fat cells?

Why does fructose cause fat-gain?

Fructose and fructose-containing foods will usually make your meals taste better, so you end up eating much more than necessary. They also fail to make you feel satisfied after you eat them, due to inadequate stimulation of leptin and ghrelin, the two satiety hormones. (6)

There is also evidence that fructose slows your metabolism: kids who drink sodas and fruit juices (both are rich in HFCS and fructose) are fatter than those who don't drink them, but who eat the same amount of calories. (7)

So, what kinds of fruits and vegetables can I eat and not get fat?

Although fruit does contain some fructose, it's not the only sugar that it contains. Fruit is beneficial for you because it's the best natural source of antioxidants that help you fight free-radicals, a major cause of aging and muscle damage. It's also an important source of fiber.

Your best bet is to choose fruits that are low in fructose, and only eat the higher fructose fruits in the morning, when your liver glycogen levels are low. At this time, your liver can use or store the fructose without converting it to fat.
fruit

The following fruits are highest in fructose (per typical serving size)*. They contain more than 4 grams of fructose per serving.

Stay away from these outside of an occasional breakfast:

? apple
? banana
? cherries (1 Cup)
? grapes (1 Cup)
? mango
? melon (2 wedges)
? orange
? pear
? pineapple (2 rings)
? watermelon (1 large slice)

These fruits are lowest in fructose; they contain less than 4 grams of fructose per serving.

You can eat these with less restriction:

? apricot
? avocado (1/3 medium; yes, it's a fruit)
? blackberries (1/2 cup)
? figs
? grapefruit (1/2 medium)
? papaya
? peach
? plum
? raspberries (1/2 cup)
? strawberries (1/2 cup)
? tomato (yes, also a fruit)

*Note, these values were calculated by adding all of the fructose plus half of the sucrose per typical serving size (i.e., a typical apple weighs 120 grams).

Vegetables are much lower in fructose than fruits. The highest fructose-containing vegetables are corn and sweet potatoes, and they only have roughly 1.2 grams of fructose per serving. If you're really trying to keep this sugar low, also avoid white potatoes and green peas.

Bottom Line:

Fructose may be one of the reasons your body is not dropping the stubborn body fat you've been fighting for weeks, or even months. Before you start avoiding the produce section of the grocery store, start scanning the labels of some of your most frequently consumed foods.

Does your salad dressing contain HFCS? Do you douse your morning eggs with HFCS-laden ketchup? Or maybe you're known to eat "all-natural" products made with honey?

Once you've eliminated these major fructose-suspects, turn to your fruit intake. Don't eliminate it completely because some fruit will aid your overall health and studliness by fighting free-radical-induced aging and muscle damage. Just choose fruits lower in fructose.

Apples may keep the doctor away, but with their high fructose content, they'll keep your six-pack just as out of sight.

Note: i'm not sure what to believe in a way the above article sounds plausible but i'm not a nutritionist and dont know what to believe. Gymjohn where u at?

All I know is if I want to do a hard weights session and then HIIT cardio from between 160 - 189bpm for 20 minutes I need to eat a banana towards the end of my weights session and have it digested 5 - 10 minutes before my run. Otherwise I feel unhealthily exhausted.

You are spot on Ryan. It depends on how lean you are too. If I eat an apple It's not gonna make me store fat. However, many overweight people do better when they eliminate fructose and all sugars as they will be insulin resistant. This means that they will convert most of their sugars to fat. A lean person will convert theirs to glycogen and store it in the muscle.

Amateur you are spot on. Consuming fast acting carbs during a session will have no bearing on fat storage. In fact doing so will help you push yourself harder which will mean more calories burned both during and after the session.

apple
banana
cherries
grapes
mango
melon
orange
pear
pineapple
watermelon

Id avoid the above listed as it will spike insulin levels leading to fat gain and suppress glucagon resulting in a postponed effect on fat loss.

We all don't need to avoid these Howard. Mainly just those going through a fat loss phase. If you are lean then the insulin spike will store the glycogen in the muscles not fat. If you've ever had a cheat day where you can literally feel your muscles swell with glycogen you'll know what I mean.

Even bulking I reckon fruit should be kept to times of insulin sensitivity such as post workout and your first meal of the day.

Your muscles don't have the specific enzymes to synthesize fructose into glycogen so must be done in the liver.The liver can only hold a limited amount of glycogen when compared to the muscles so when liver glycogen is full an enzyme responsible for glucose regulation signals to the body that glycogen levels are full and so the fructose is easily converted to fatty acids and stored as body fat.
Personally if I was to choose fruit Id stick with berries or have the odd green apple(with skin).

gym john-i'm approaching my last week on a cut -i havn't added honey or maple syrup into my diet yet but was thinking of doing so as they are low g.i (but also high in fructose)
will the addition of fructose carbs make a difference to fat loss?

Ryan the amount of honey you'd put on museli or porridge r whatever wouldn't really be that significant. U only need a small amount as its a strong(delicious

) taste.besides ur article says u can eat fructose in the mornin. just don't slosh it on. Nd if ur approaching ur last week of a cut y not just leave it out till ur finished.I personally don't believe fruit will make u fat but I only really eat it round bfast nd pwo anyway.if ur worried it'll hinder fatloss just leave it till u finish cutting. This controversy with fruit is alot like with milk. People are pro fruit and against fruit just like people are pro milk or against it

if all else fails look at the facts

http://en.wikipedia.org/wiki/Fructose_malabsorption