75 Grams Of Walnuts A Day Was Linked To Better Sperm Quality
Tim Ferriss said he tried to fact-check a testosterone claim and got no confirmation, finding sperm quality research instead.
The Tim Ferriss Show · #886: The Random Show — AI Super Assistants, Boner Pills, Dream Engineering, Wizards, Supplements, Books, and MoreEating about 75 grams of walnuts a day was linked to better sperm vitality, motility, and shape.
In a 2012 randomized trial, 117 healthy men ages 21 to 35 either kept their normal diet or added 75 grams of walnuts daily.
That is about six-tenths of a cup of chopped walnuts, or roughly two and a half handfuls.
The walnut group showed statistically significant improvement in vitality, meaning more live sperm. Motility also improved, meaning better swimming ability. Morphology improved as well, meaning more sperm with a normal shape.
A 2024 combined analysis found a similar pattern with at least 60 grams of nuts daily, or about two handfuls. It improved vitality, motility, and shape, but not sperm concentration. Nuts are calorie dense, so extra handfuls can add substantial calories.
Author and investor Tim Ferriss, who said he was looking into fertility because he hopes to have children, said he had heard that walnuts could improve testosterone and tried to check the claim. He said he got no confirmation back, but found the sperm quality research instead.
Questions people ask
What do vitality, motility, and morphology mean?
Vitality means the share of sperm that are alive. Motility means how many move well and swim forward. Morphology means how many have a normal size and shape.
How many calories are in 75 grams of walnuts?
About 490 calories, along with about 11 grams of protein and about 49 grams of fat. That is roughly one quarter of a day's calories on a 2,000 calorie diet, so it can displace other foods if added without adjustment.
Does this prove walnuts improve fertility?
No. The 2012 study was randomized and controlled, which is stronger than an observation, but it was small and studied healthy young men. Larger, longer trials in more diverse men would be needed to know how general and lasting the effect is.