Do 'natural' testosterone boosters actually work for men?

What did @drew.review actually say?

In a video with over 735,000 views, @drew.review — self-described as a "pancreatic cancer researcher and naturopath practitioner" — recommended four supplements for raising testosterone: Tongkat Ali, Shilajit, Pumpkin Seed Oil, and Ashwagandha. He claims Tongkat Ali "releases testosterone from its bound state," that Shilajit "may directly stimulate testicular function," and that Pumpkin Seed Oil prevents testosterone from converting to DHT. The video ends with a paid promotion for a "15-in-1 testosterone booster formula" from a brand called Micro-ingreins.

The framing is that these are "scientifically backed" interventions. That claim deserves scrutiny, because the evidence behind these supplements ranges from modest to thin, and the mechanisms described are sometimes oversimplified or outright wrong.

Does the science back this up?

Partially, but the effect sizes are small and the human trial data is limited. Tongkat Ali and Ashwagandha have the most credible evidence of the four. Shilajit has some promising but small-scale data. Pumpkin Seed Oil's testosterone-related claims are largely extrapolated from its zinc content and prostate studies, not direct hormone research.

On Tongkat Ali: a randomized trial by Leisegang et al. (2022, Andrologia) found supplementation increased free testosterone in men with late-onset hypogonadism. The mechanism isn't simply "releasing bound testosterone" — it likely involves inhibiting sex hormone-binding globulin (SHBG) and reducing cortisol. The distinction matters because the creator's explanation implies a simpler on/off switch that doesn't match the biology.

On Shilajit: Pandit et al. (2016, Andrologia) found 250mg twice daily increased total testosterone by about 23% in healthy male volunteers over 90 days. That's a real finding, but it was a small trial (75 men) and hasn't been widely replicated.

On Ashwagandha: Lopresti et al. (2019, Medicine) and Wankhede et al. (2015, Journal of the International Society of Sports Nutrition) both found modest testosterone increases alongside significant reductions in cortisol. The stress-cortisol-libido connection the creator describes is legitimate physiology.

What did they get wrong (or right)?

The Pumpkin Seed Oil claims are where the video goes most sideways. Saying it "prevents testosterone from being converted into DHT" is misleading. That mechanism is associated with 5-alpha reductase inhibitors like finasteride, not pumpkin seed oil. Pumpkin seed oil has shown benefit for benign prostatic hyperplasia symptoms (Vahlensieck et al., 2015, Urologia Internationalis) and has some data on hair loss, but framing it as a DHT blocker comparable to pharmaceutical inhibitors overstates what the evidence supports.

The zinc point is fair — zinc deficiency is associated with lower testosterone (Prasad et al., 1996, Nutrition), and pumpkin seeds do contain zinc. But if you're not deficient, supplementing zinc won't move your testosterone numbers much.

The Ashwagandha section is actually the most accurate part of the video. The cortisol-testosterone relationship is real. Chronic stress elevates cortisol, which suppresses luteinizing hormone and therefore testosterone production. Ashwagandha's adaptogenic effects on the HPA axis are among the better-documented claims in this space.

The paid promotion at the end is the biggest red flag. A "15-in-1 testosterone booster" with no disclosed dosing information and a "flash sale" call-to-action is a classic supplement marketing pattern. Stacking 15 ingredients at unknown doses in a single capsule is not how any of these compounds were tested in the studies cited.

What should you actually know?

If your testosterone is clinically low, these supplements are not a substitute for proper diagnosis. Low testosterone (hypogonadism) requires a blood panel, not a TikTok shopping cart. None of these supplements have been shown to restore testosterone to normal levels in men with confirmed hypogonadism.

For men with levels in the low-normal range who want to optimize, sleep, resistance training, body fat reduction, and alcohol reduction have more consistent evidence than any supplement on this list. Leproult and Van Cauter (2011, JAMA) showed that one week of sleep restriction to 5 hours reduced testosterone by 10-15% in young men. That's a bigger effect than most of these supplements show in trials.

If you're on medication, the creator's closing disclaimer to "check with your healthcare provider" is appropriate. Ashwagandha in particular has interactions with thyroid medications and immunosuppressants. This isn't a trivial warning to tack on at the end of a sales pitch.

The bottom line: some of these ingredients have real, modest evidence behind them. But the mechanism descriptions are often oversimplified, the Pumpkin Seed Oil DHT claim is not well supported, and the whole video is framed around selling a specific product. Treat the recommendations with that conflict of interest in mind.