What you eat can be an ally or saboteur when it comes to your health, but the difference isn’t always so cut and dry. Some diet advice is clear—avoid scarfing too many fried wings and chips, load up on veggies, and always eat your greens. But several trendy eating styles that promise weight loss or muscle gain look good in theory, but can actually tank your testosterone in the long term.
Testosterone supports muscle, drive, mood, and long-term vitality. Push your diet to extremes, and it can leave you feeling sluggish, moody, bloated, and beyond. Researchhighlights several popular approaches that can backfire, including overexertion on protein, excessive consumption of ultra-low-fat foods, calorie restriction that is too severe, and prolonged fasting, which can spike stress hormones that counteract testosterone. Additionally, falling short on zinc, magnesium, or vitamin D doesn’t help either.
To sort what actually works, we asked top physicians and nutrition pros where men get tripped up, and how to eat for strong, steady testosterone instead.
Low-Fat Diets Can Blunt Testosterone
Going too low in fat might seem like a smart move for heart health or weight loss, but cutting it too low can backfire on your hormones. Both clinicians and researchers say this is a pretty common occurrence when it comes to low T.
“Eliminating good fats is the biggest dietary mistake men can make, which lowers their testosterone,” says Dr. Meena Malhotra, a double board-certified physician in Internal Medicine and Obesity Medicine.
When men cut fat in pursuit of weight loss, they’re forgetting that testosterone is “synthesized from cholesterol, which is fat-based,” explains Dr. Justin Houman, an assistant professor at Cedars-Sinai Medical Center, specializing in men’s health and fertility.
In other words, restricting fats, especially healthy ones, can limit the body’s ability to produce hormones. This explains research findings showing men on very low-fat diets had significantly lower testosterone compared to those eating moderate or higher-fat diets.
So, instead of fearing fat, leave 25–35 percent of your daily calories for fat, with an emphasis on foods like fatty fish, nuts, seeds, olive oil, and avocado. Foods packed with unsaturated fats support testosterone production while giving you a dose of anti-inflammatory benefits that protect your health for the long run.
Extreme Fasting and Calorie Restriction Raise Stress Hormones
Intermittent fasting can be a useful tool, but pushing it too far may backfire on hormone health. Research shows that cutting your calories too low, or fasting for too long, raises cortisol, the body’s primary stress hormone, which in turn suppresses testosterone production.
Licensed dietitian Thomas Prather, founder of Gut Brain Body Functional Nutrition, says most of his patients who struggle to produce enough T have been eating too low in calories for too long. “This is generally coupled with higher stress levels and poor quality sleep, which keeps them in a state of adrenal overdrive,” he explains. In his view, long-term or excessive fasting is “at the top of my list” of dietary mistakes tied to low testosterone.
If you want to stick to fasting, Houman stresses keeping it moderate to avoid doing more harm than good. “When men push it to extremes with very long fasts or minimal eating windows, it can increase stress hormones and drop testosterone,” he says.
The takeaway: time-restricted eating can work if done moderately, but chronically undereating or stretching fasting windows to extremes sets up a hormonal environment where testosterone takes a hit.
Related: This Protein Shake Packs 36 Grams of Muscle-Building Power—and Tastes Like Pumpkin Pie
Ultra High-Protein Diets Can Backfire
Protein is often seen as the cornerstone of muscle-building nutrition, but going overboard may quietly drag down testosterone. A recent meta-analysis found that consuming over 3.4 grams of protein per kilogram of body weight per day led to a significant drop in men’s testosterone.
To put that in perspective, a 180-pound man would need to consume nearly 290 grams of protein daily to hit this threshold, an intake far beyond what most people—even athletes—typically reach.
“This is not a typical amount of protein and is difficult to achieve,” explains Malhotra. Instead, she recommends moderate to high protein intakes, which support fat loss and muscle growth without risks of lowering your T.
“Men sometimes chase muscle gains and eat huge amounts of protein while cutting carbs too low,” says Houman. But overindulging in chicken breast and protein shakes at the expense of carbohydrates and fats disrupts hormonal balance, he says. This causes the body to boost nitrogen waste removal, raising cortisol levels and blunting testosterone production.
The sweet spot? Research suggests most active men thrive on 1.6–2.2 g/kg/day of protein, which is enough to support muscle growth and recovery without tipping testosterone into decline.
Carb-Cutting Gone Too Far
Carbs aren’t the enemy, but popular diets have painted them that way for years. The problem shows up when intake gets so low that it cranks up stress hormones and blunts the anabolic response to training. A systematic review found that low-carb diets raise resting cortisol in the first weeks and keep post-exercise cortisol elevated. And if you pair low carb with very high protein, both resting and post-workout testosterone can drop.
Clinically, that tracks with what experts see. Prather says that outside of ketosis, very low-carb often backfires: “low carb diets are the most common and most correlated with low testosterone levels,” adding that under-fueling the brain and thyroid “driv[es] a state of metabolic stress” and ramps cortisol.
The fix is to keep carbs in play, especially around training, to steady the stress response and support performance. Houman suggests most active men should save 40–50% of their daily calories for carbs. The research echoes this, showing that having carbs available during exercise helps tame the cortisol surge after long sessions.
Micronutrient Deficiencies That Sap Testosterone
Micros matter too. Studies show that low levels of vitamin D, zinc, and magnesium are strongly linked with lower testosterone, and these nutrients help with everything from making testosterone in the testes to shuttling hormones where they need to go. These nutrients influence everything from testosterone synthesis in the testes to the way hormones are transported and used in the body.
Deficits show up most in restrictive eaters. Houman notes, “The most common deficiencies I check for are vitamin D, zinc, magnesium, and sometimes selenium, and men with restrictive diets…are at higher risk.” Prather flags low omega-3s and skimpy antioxidants for driving oxidative stress that can stall testosterone production, adding that “supplementing with vitamin D, and also zinc in individuals that are deficient,” can move the needle.
Aim for a variety of nutrient-dense foods like seafood, nuts, seeds, legumes, leafy greens, and fortified dairy or plant milks, and use targeted supplements only if labs show you’re low. Cover these basics so your macros can actually support steady hormone balance.
Related: The 8 Dietitian-Approved Foods That Can Naturally Boost Testosterone
Alcohol and Processed Foods Fast Track Inflammation
Heavy drinking and a steady stream of packaged foods ramp up oxidative stress, metabolic dysfunction, and systemic inflammation, both of which chip away at hormone production. Men who lean on ultra-processed options also tend to fall short on antioxidants and key nutrients, a combo tied to lower testosterone.
Prather points out that sugar and inflammatory fats can add fuel to the fire, especially if you don’t get enough exercise. He adds that the problem often stems from “the lack of antioxidant intake and the inflammation that those foods produce.”
You don’t have to cut out treats entirely, but be aware of your habits. Limit alcohol and ultra-processed picks, and load up on fruits, vegetables, nuts, and omega-3–rich fish. You’ll bring in the antioxidants and healthy fats that help calm inflammation and protect hormone balance.
Final Word on Testosterone and Diet
Diet won’t stop the age-related dip in testosterone, but it can soften the slide. Push too far by slashing fat, piling protein sky-high, or cutting carbs hard, and you crank up stress and chip away at hormone health.
Experts stress a steady, balanced approach. Eat enough to fuel your day, keep healthy fats in play, aim for moderate protein, and include quality carbs (especially around training). Cover the basics with nutrient-dense foods rich in vitamin D, zinc, magnesium, omega-3s, and antioxidants, and keep alcohol and highly processed foods in check.
Testosterone isn’t a growth lever you can hack; it’s part of a system that thrives on consistency. By keeping your diet balanced and sustainable, you give your hormones the foundation they need to support strength, energy, and long-term health.
