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Too much cholesterol in sperm makes it harder for them to get ready to fertilize an egg, because it stops key changes they normally need to make.
Too much cholesterol in sperm cells stops them from becoming more flexible when they need to, which stops them from activating the internal signals needed to swim powerfully toward an egg.
Sperm that don't swim well have much more cholesterol and a related molecule called desmosterol than good swimmers, and they can't make their outer membrane more flexible when they're getting ready...
Sperm cells with too much cholesterol and a similar fat called desmosterol don't move as well when they're getting ready to fertilize an egg, and this might be because those fats mess with their...
When doctors remove extra cholesterol from the muscle cells in the gallbladder of people with gallstones, the gallbladder starts contracting better again—this means the amount of cholesterol in those...
People with gallstones made of cholesterol have stiffer cell membranes in their gallbladder muscles, which might make the gallbladder less able to squeeze and empty properly.
After a workout, drinking a protein and carb shake keeps a key muscle-building signal active for longer than just working out alone—this might help muscles grow better.
When you lift weights and then eat a protein-rich meal with some carbs, your muscles build more protein than if you just did the exercise or just ate the meal alone — it’s like the two work better...
If young men who don't usually work out drink a special protein-and-sugar shake about an hour after lifting weights, their muscles build protein much faster—nearly triple the rate—compared to just...
After working out, drinking a special protein and sugar shake helps your muscles start building more efficiently by turning on key signals inside your muscle cells, better than just working out alone.
If young men who don’t usually lift weights drink a special protein-and-sugar shake one hour after working out, their muscles build protein much faster—nearly triple the rate—than if they just worked...
Even without added leucine, a shake made from pea and canola protein can boost muscle building by more than 175% compared to when you're fasting — meaning plant-based proteins might work just as well...
Eating 20 grams of whey protein and 20 grams of a plant-based protein with added leucine both build muscle at about the same rate in young, healthy people—even though whey makes your insulin spike...
Adding a little extra leucine to a plant-based protein shake makes your body absorb more leucine and builds more muscle compared to the shake without it, which means leucine was the missing piece...
If you're a healthy young adult, eating 20 grams of plant protein from peas and canola will help your muscles grow a little after fasting, but not as much as drinking whey protein — so animal-based...
If you're a healthy young adult, eating a plant-based protein shake with extra leucine can build muscle just as well as a whey protein shake, as long as both have the same essential amino acids — the...
Scientists found that we lose more nitrogen through our skin than previously thought—about three times more. This means the old guidelines for how much protein we need might be too low.
A long-standing guideline says people should eat 0.57 grams of egg protein per kilogram of body weight each day, but this study suggests that might not be enough to keep healthy young men’s bodies in...
When young men drank more skim milk powder to get more protein, their liver enzyme levels went back to normal quickly—this might mean that not getting enough protein can stress your liver early on.
Eating just 0.59 grams of egg protein per kilogram of body weight every day isn't enough to keep your body in good balance over time—it can cause your body to lose muscle and potassium, even if...
Birds exposed to a certain chemical have eggs that vary more in size from one to another in the same nest, but the average size of the eggs is about the same as in birds not exposed to the chemical.
The longer a female kestrel eats food with toxic chemicals called PCBs, and the later she lays her eggs, the more of those chemicals end up in her eggs.
When captive American kestrels eat food contaminated with PCBs at a certain dose, their egg yolks get heavier and the clear egg white part gets smaller, which might mean the baby birds inside don't...
Eating whole eggs after a workout helps your muscles rebuild faster than eating just the egg whites, even if both have the same amount of protein — the fat and other parts in the whole egg seem to...