Seed Oils and Testosterone: Should You Actually Avoid Them?

If you spend any time in online health and fitness communities, you have almost certainly encountered the claim that seed oils are destroying your health and tanking your testosterone. The messaging is often dramatic: seed oils are portrayed as a modern poison, responsible for everything from obesity to hormonal collapse. As with most viral health claims, the reality is more nuanced than the headlines suggest.

What Are Seed Oils and Why the Controversy

Seed oils (sometimes called vegetable oils) are oils extracted from the seeds of plants, often with solvents and heat. The most common include soybean oil, canola oil, corn oil, sunflower oil, safflower oil, and cottonseed oil. These oils are relatively high in omega-6 polyunsaturated fatty acids, particularly linoleic acid.

The controversy centers on a few interconnected concerns. First, omega-6 fatty acids can be converted in the body into signaling molecules involved in inflammation. Second, some researchers argue that the Western diet has shifted toward far more omega-6 relative to omega-3 than ancestral diets, though the usefulness of this ratio is itself debated. Third, these oils are often industrially refined and found in fried and ultra-processed foods. Critics argue this combination promotes systemic inflammation, which in turn may suppress testosterone.

The Theoretical Pathway: Omega-6, Inflammation, and Testosterone

The middle step is biologically real: a review of immuno-endocrinology of the testis describes how pro-inflammatory cytokines such as IL-1 and TNF released by activated macrophages inhibit Leydig cell steroidogenesis.^[4] That work is mostly from cell and animal models. It tells us inflammation can matter for testosterone, which fits with our article on stress, cortisol, and testosterone. It does not tell us that normal dietary seed oil intake triggers that inflammation.

On the first step, the human data are reassuring. A systematic review of randomized controlled trials in healthy people found that none of 15 studies reported significant effects of higher linoleic acid intake on a wide variety of inflammatory markers, including C-reactive protein, fibrinogen, cytokines and TNF-alpha. The reviewers concluded that virtually no randomized evidence shows that adding linoleic acid to the diet raises inflammatory markers in healthy people.^[1]

What the Evidence Actually Shows

When you look for direct human studies of seed oil intake and testosterone, you find very little. Most of the evidence cited in anti-seed-oil content is from animal or cell studies, or from observational data about inflammation that does not isolate seed oils.

What does exist is a mixed picture on dietary fat in general:

• A cross-sectional study of 209 healthy young Spanish men reported that higher omega-6 intake was associated with higher luteinizing hormone (LH) and smaller testicular volume, that omega-3 intake was associated with larger testicular volume, and that trans fat intake was associated with lower testosterone. Monounsaturated fat intake, surprisingly, was inversely associated with testosterone. This was a single cross-sectional study, so it shows associations only, not that any fat caused the differences.^[5]
• A meta-analysis of intervention studies found that low-fat diets appeared to decrease testosterone compared with high-fat diets, but the authors noted that more randomized trials are needed.^[2] This is a reason not to cut fat too low, not a reason to choose one oil over another.
• In a 3-week study of 60 healthy Moroccan men, replacing butter with extra virgin olive oil or argan oil was followed by higher testosterone and LH (about 17% and 20% higher testosterone for olive and argan oil respectively). There was no placebo group, the sample was small, and the study was short, so it is best read as a hypothesis-generating result.^[6]

We also know that very low-fat diets tend to reduce testosterone, as discussed in our nutrition and testosterone guide. Adequate dietary fat supports the body's normal hormone production, so the goal is enough fat from good sources rather than fearing one category of oil.

The Social Media Amplification Problem

The anti-seed-oil movement has been amplified enormously by social media, where nuanced takes do not perform well and absolutist positions generate engagement. Statements like “seed oils are destroying your testosterone” get shared far more than “the evidence on seed oils and testosterone is limited, and your overall dietary pattern matters more than any single ingredient.”

This creates a distorted perception of risk. Men who eat an otherwise excellent diet with good sleep, regular training, and healthy body composition are unlikely to have their hormones meaningfully affected by occasional seed oil exposure. Yet the online discourse can lead to anxiety about ingredients that may not warrant that level of concern.

This is not to say that choosing your fat sources is a bad idea. It is not. Cutting back on deep-fried and ultra-processed food (where refined seed oils are common) is a sensible move for many reasons. But the framing matters: improving your overall diet is evidence-based; believing trace amounts of seed oil are destroying your hormones is not.

What About Heart Health?

It is worth keeping the bigger picture in view. In a pooled analysis of 30 prospective studies with 68,659 participants, higher circulating and tissue levels of linoleic acid (a marker of intake) were associated with lower risk of total cardiovascular disease, cardiovascular mortality and ischemic stroke.^[7]The American Heart Association's presidential advisory on dietary fats concluded that randomized trials replacing saturated fat with polyunsaturated vegetable oil reduced cardiovascular disease by about 30%, and recommended replacing saturated fat with unsaturated fat, especially polyunsaturated fat.^[3]

This is why we do not recommend loading up on butter, ghee or coconut oil in the name of testosterone. Saturated fat is fine in moderation, but there is no good evidence that it raises testosterone in men eating adequate fat, and heart health guidance points the other way. If you have high cholesterol or heart disease risk factors, ask your doctor about your fat intake.

Which Oils to Prefer (and Why)

The practical approach is straightforward: prioritize fats from whole foods and less processed oils, without developing anxiety about occasional exposure to less-ideal options.

Extra virgin olive oil is an easy default. It is rich in monounsaturated oleic acid, contains polyphenols, and fits the Mediterranean-style eating pattern that heart health guidance recommends. Use it for dressings and everyday cooking. Avocado oil has a similar fat profile with a higher smoke point. Small amounts of butter or ghee are fine in a balanced diet and provide fat-soluble vitamins (see our article on vitamin K2), but they do not need to be the centerpiece.

Practical Recommendations

The Bottom Line

Should you believe that seed oils are the primary driver of testosterone decline? No. That claim far outpaces the available evidence, and randomized trials do not show that linoleic acid drives inflammation in healthy people.

Should you still think about food quality? Yes. Eating more whole foods, using olive oil as an everyday default, and cutting back on fried and ultra-processed food are reasonable choices on their own merits.

The most effective strategy for supporting healthy testosterone remains a comprehensive approach that addresses sleep, training, nutrition quality, stress, body composition, and environmental exposures. You can find a fuller list of dietary patterns to watch in our guide to foods that may work against testosterone.

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