“Improving insulin resistance may support weight and blood sugar control, especially in people with prediabetes or metabolic syndrome. That said, black seed oil is not a weight loss solution on its own,” Dr. Ostfeld adds. He points out that, like any oil, black seed oil is calorie-dense (about 120 calories per tablespoon), so consuming it in large amounts can work against weight loss goals. “Sustainable weight loss still comes down to a healthful lifestyle: nutritious eating, regular movement, good sleep, and in some cases, medications that target metabolism,” he says.
The claim: It can reduce Irritable Bowel Syndrome symptoms.
The reality: If you have irritable bowel syndrome, popping a black seed oil capsule or incorporating the oil into your diet could help reduce your symptoms—especially if your biggest IBS symptom is diarrhea.
“There’s evidence that black seed oil may assist with IBS symptoms like diarrhea because it has anti-inflammatory and tummy-soothing qualities that ease gut irritation and promote a healthier microbiome,” Schiff says. That said, there has been only one study on this, so more research needs to be done.
Shida Haghighat, a gastroenterologist at UCLA says that while human research on black seed oil and gastrointestinal conditions is limited, its aforementioned active ingredient, thymoquinone, has shown some promise.
“Limited studies have shown people with IBS experienced improvement in symptoms after six weeks of taking black seed oil,” says Dr. Haghighat. “There have been studies that show that thymoquinone can help with various disorders of the stomach such as acid reflux, dyspepsia, gastritis, conditions more commonly known as heartburn, upset stomach, indigestion, and bloating.”
But she warns that taking black seed oil may also come with some uncommon side effects, including nausea, bloating, and diarrhea.
“I would caution whoever is thinking about taking it to check with a doctor first for potential drug interactions as it can alter the metabolism of other medications,” Dr. Haghighat says.
The claim: It’s good for your prostate.
The reality: Maybe you’ve heard that black seed oil can lower your risk of prostate cancer or support male fertility. This is one area where the science just isn’t there yet to prove a connection.
One of the most common black seed oil benefits for men you’ll come across is that it can improve sperm quality. While Bergner says that there is one well-done human scientific study from 2014 that showed that black seed oil improved sperm quality, it hasn’t been replicated since then. Urologist Daniel Brison, also says that the existing data on black seed oil for male fertility is promising, showing that consuming black seed oil led to producing more testosterone and sperm. Still, more research needs to be done.
As for the link between black seed oil and improved prostate health, again, not enough research exists to prove it. That said, Bergner points out that since black seed oil is anti-inflammatory, it isn’t too much of a leap to believe that it can reduce the risk of prostate cancer, just as it does other types of cancer.