Six Star Testosterone Booster is generally safe for healthy adult men when taken as directed. Its three active ingredients, rhodiola extract, ginkgo extract, and boron citrate, are well-studied compounds with established safety profiles at typical supplement doses. That said, “safe” depends on your health status, what medications you take, and whether you follow the dosing instructions. Here’s what you need to know before taking it.
What’s Actually in It
The formula contains two groups of active ingredients. The first is an “anti-catabolic complex” made up of rhodiola extract and ginkgo extract, two herbal ingredients commonly found in stress and recovery supplements. The second is a “free testosterone stimulator” consisting of boron citrate, a mineral compound.
None of these are hormones. Unlike prescription testosterone, this product doesn’t introduce synthetic testosterone into your body. Instead, it uses plant extracts and a trace mineral that may modestly influence your body’s own hormone balance. This is an important distinction: the safety concerns here are very different from those of actual testosterone therapy.
How Boron Affects Testosterone
Boron is the ingredient doing the heavy lifting for the testosterone claim. Research published in the Journal of Trace Elements in Medicine and Biology found that after one week of daily boron supplementation, men’s free testosterone levels increased while estradiol (a form of estrogen) decreased. A separate clinical trial found that boron supplementation roughly doubled testosterone concentrations in postmenopausal women taking 3 mg per day for seven weeks.
These are real effects, but they’re modest in the context of a healthy young man who already has normal testosterone levels. If you’re expecting dramatic muscle gains from boron alone, the evidence doesn’t support that. The changes are measurable in blood work but unlikely to produce the kind of transformation you’d see from, say, resistance training or improved sleep.
Boron Safety and Upper Limits
The National Institutes of Health sets the tolerable upper intake level for boron at 20 mg per day for adults 19 and older. Six Star’s directions call for two caplets twice daily (four caplets total), and as long as the boron content per serving stays below that 20 mg ceiling, daily use falls within accepted safety margins.
Boron toxicity is real but requires extremely high doses. Symptoms of excessive boron intake include nausea, diarrhea, skin flushing, headache, and restlessness. Severe toxicity can cause kidney damage and, at doses of 15,000 to 20,000 mg, can be fatal. You’re nowhere near those levels with a standard supplement dose, but exceeding the recommended four caplets per day is not worth the risk.
Ginkgo Extract and Bleeding Risk
This is the most important safety concern in the formula, and it applies to a specific group of people. Ginkgo biloba has well-documented interactions with blood-thinning medications. A comprehensive analysis published in PLOS One found that ginkgo frequently interacts with antiplatelet drugs, anticoagulants, and common anti-inflammatory medications. Aspirin and clopidogrel showed the highest interaction rates, and medications like celecoxib, loxoprofen, and nifedipine were also significantly associated with increased bleeding risk when combined with ginkgo.
If you take any blood thinner, antiplatelet drug, or even regular doses of over-the-counter anti-inflammatories like aspirin or ibuprofen, the ginkgo in this product could amplify their effects and raise your risk of abnormal bleeding. This also applies if you have a bleeding disorder or are scheduled for surgery. For healthy men not taking these medications, ginkgo extract at supplement doses is not a major concern.
Who Should Avoid It
Any product marketed as a testosterone booster deserves extra caution if you have a hormone-sensitive condition. The Mayo Clinic lists prostate cancer (known or suspected) and male breast cancer as conditions where testosterone-influencing products should not be used. While Six Star isn’t prescription testosterone, the principle still applies: if your doctor has told you to avoid anything that could raise testosterone levels, skip this supplement.
Men with kidney problems should also be cautious, since boron is processed through the kidneys. And because the formula contains ginkgo, anyone with a history of easy bruising, bleeding disorders, or upcoming surgical procedures should avoid it or discuss it with their doctor first.
Common Side Effects
Most users tolerate the product without issues. The side effects that do get reported tend to be mild and digestive: stomach discomfort, nausea, or loose stools, particularly when taking the caplets on an empty stomach. Taking your serving with food and a full glass of water, as the manufacturer suggests, helps reduce this.
Rhodiola can occasionally cause dizziness or dry mouth, and ginkgo may cause headaches in some people. These effects are dose-dependent and typically resolve when you stop taking the product or reduce your intake.
How to Take It Safely
The manufacturer recommends one serving (two caplets) with water, twice daily, for a total of four caplets per day. They explicitly state not to exceed four caplets in a 24-hour period. Consistent daily use is recommended for ongoing effects on muscle performance and endurance.
A few practical guidelines will help you stay in the safe zone:
- Don’t double up on missed doses. If you skip a serving, just take your next one as normal.
- Take it with food to minimize stomach irritation.
- Review your medication list. If you take anything that affects blood clotting, including daily aspirin, the ginkgo in this product may not be compatible.
- Watch for changes. Unusual bruising, prolonged bleeding from small cuts, or persistent digestive upset are signals to stop and reassess.
The Bottom Line on Effectiveness
Safety and effectiveness are separate questions, but they’re connected in practice. The boron in this product has some clinical backing for modest increases in free testosterone. The rhodiola and ginkgo may help manage the cortisol response to exercise, which could indirectly support a better testosterone-to-cortisol ratio after training. But none of these effects are dramatic, and the product won’t substitute for the fundamentals: consistent strength training, adequate sleep, proper nutrition, and maintaining a healthy body weight. Those factors influence your testosterone levels far more than any over-the-counter supplement.
For a healthy man with no contraindications, Six Star Testosterone Booster is a low-risk product at its recommended dose. The ingredients are well within established safety limits, and the most meaningful risk, the ginkgo-blood thinner interaction, only applies if you’re on specific medications. It’s one of the more straightforward testosterone boosters on the market, with a short ingredient list and no exotic compounds that lack safety data.