T Nation

Glucose Can Lead to Low Testosterone?


Lol! That’s worth an eating contest. Apples KILL my appetite like nothing else calorie per calorie


I recall in the 1980s John Parillo used to preach a fructose free diet, and that was when high carbs were fashionable. He stated he got this through his wife’s medical books, rat studies, etc, and anthropological theories based on rotund Polynesian tribes who subsist on high fructose diets, etc.

If this leads to fat gain, then said gain is linked to hormone issues. There is a direct relationship between obesity and hormone issues. This is not in dispute.


this is funny cause when i was i army, they gave as apples every morning to raise appetite, especially for those little guys that needed to pack on muscles


Excess fructose is a direct cause of liver insulin resistance. The fructose you eat has to go to the liver because it is very harmful in the bloodstream (fructose has 10 x the effects on A1C as glucose in the bloodstream). Since fructose has to go to the liver, a large dose will pound the liver and the liver can’t turn it all into glycogen, and so it has to use a different pathway that leads to citrate which gets turned into liver fat.

But since fructose goes straight to the liver it is a good way to reload liver glycogen after exercise. Without exercise, the liver can only turn about 25 grams of fructose into glycogen per day, before raising triglyceride levels and liver fats.

Fructose can only do three things in the body: 1) it can be turned into liver glycogen; 2) it can be turned into liver fats/blood triglycerides; 3) if can leak into the bloodstream in tiny amounts (about 1 mg/dl) where it has the same effect on A1C as 10 mg/dl of added blood sugar (it can raise A1C by about .3 to .4 without any change in blood glucose levels).

This is most significant for people who also drink alcohol, and also for sedentary folks/kids drinking 64 oz super big gulps 10 pump lattes, and boxes of sweetened breakfast cereal.

Fruit sugar is half fructose, combined with fiber that slows the entry into the liver.

The short term issues of testosterone and glucose are not pathological. It is only seen in the 2 hour window after eating carbs. Low carb and low fat diets can both lead to low testosterone.

The O.P.s diet looks good and I see nothing that would cause low T. Carbs are at about 50% and fats around 25% so MAYBE could add a little fat but its not killing T levels.


first, I´m not a vegan, not nearly! Second, I don´t have anything against vegans! Third, for me, diet is not my religion like for some other people! I only want to know more about nutrition and I´m interested in this whole diet crap.

What about the vegans, who are “sedentary” or don´t be as active as a regular fit person when they eat tons of fruit everyday or in general a shit load of carbs? Is this also harmful for the body? Why?


I can’t find a way to justify a sedentary low fat fruitarian lifestyle for health and performance.


you did mention nuts reduce t. i do eat 1 serving of pb and 1 serving of cashews


I said that they can raise cortisol. This is because they are high in omega-6 and also some people are sensitive to nuts similarly to grains. Your not “living” in peanut butter and cashew so looking at your entire diet, that is not tanking test. You might have a good allergy though. Some people can NOT process fructose at all and can get very sick from it. Do you feel bad with any foods?


yeah my cortisol is not that high. i overthink a lot and have stress. cortisol tested in 7 am.

i have runny nose in every meal actually but for some reason i have more runny nose when eating something cold or hot. i get the runny nose when eating everything even veggies.

also i have low igf1 low dhea estradiol of 5


But even if you sit on your butt all day doing nothing, your liver glycogen is always being used rather than muscle glycogen for energy. So the 25g number is wrong. I’ve seen the number of 5g of glycogen being used per hour while sleeping. We enter lipolysis/ketosis after a full night of sleep when the liver glycogen is depleted.

Studies show 60g of fructose being absolutely fine in sedentaries. Most likely 50g used up per hour of (anaerobic?) training.

There’s a large amount of fruits we can eat, and fructose prevents blood sugar spikes. That is unless you drink a boatload of smoothie with multiple bananas in it. On a regular whole fruit base (and tubers) (and less than 15% dietary fat) I got hbA1c down from 6.1 to 5.4%, glucose and insulin levels near optimal (HOMA-IR score 30), test levels back in range after 2 years of TRT+orals. Trigs below 100 of course as always.

Most of the “science” on fructose applies to people who drink massive amounts of trash at once. Eat fruit nothing happens, you’ll get satiated unless hunger signaling is impaired. Thank god im not leptin resistant myself.


I’ll add that most fructose gets turned into glucose by the gut organs that have enzymes that do that conversion. I can’t say what the level for harms is but there is no evidence of harms at under 25 grams of fructose per day which would be about 3-4 bananas. Only 30-50% of the carbs in fruit are net fructose, while 50-70% is net glucose.

Also, I concur, at rest you use about 5-6 grams of glycogen up per hour. The problem is if it comes in at overload rates in a short period of time. Then the gut organs are not turning much into glucose. Plus, if liver glycogen is already topped off from glucose, fructose still has to go to the liver to keep it out of the bloodstream where it is highly glycosylating. A super big gulp is giving you 75 grams of fructose in short order. Also problematic with alcohol. One drink is 20 grams of alcohol which overloads the same pathways as fructose.

You could burn 50 grams of liver glycogen in an hour at a moderate pace (around 500 calories per hour). And you could fully reload that with fructose.


I definitely agree that fruit intake could be tricky to properly do. I mostly snack during the day, fruit as in one or two at a time, protein&veggies meal

Always very laughable when raw fruitarians / vegans / whatever they label themselves come up with triple digits triglycerides if not 200+ mg/dL. Nope, we didn’t evolve to drink a half watermelon and bananas and kiwis and all that “healthy” buncha green stuff in one go.


@tontongg soooo if i eat 80 grams of sugar from fruits before bed ill be risking my health and test?


I am just going to say yes at this point.



sorry not trolling but explain? then why vegans and fruit eaters have good health? im just confused and dont even know what to eat anymore


It looks like you REALLY want someone to tell you that eating glucose and fruit is bad for you, so I did it.



well fruits= glucose. its just something im worried but ill stop.


Fruits also = fructose which = glucose.

I like math too.



i just read that in google. sorry im new to fructose and all of this. thats why im actually posting here, to learn from you guys. no need to be rude btw


I apologize if you feel I am being rude. That is not my intent. I thought we were both educating each other on fruit.