Biohacker Bryan Johnson has shared his perspective on the popular AG1 supplements, expressing skepticism by stating they offer ‘no clinical benefit.’

At 48, Johnson, who asserts his biological age is over ten years younger, has drawn attention to a clinical study focused on Athletic Greens (AG1). This widely endorsed supplement powder is famous among influencers for its promises to enhance gut health, increase energy, bolster immune function, and bridge nutritional gaps.

Johnson, an advocate for taking more than 100 supplements daily to reduce his biological age, cautioned against the use of AG1, advising his audience to ‘cancel your subscription.’

He referenced a clinical trial from 2024 that resurfaced, involving 30 healthy adults. In this study, half of the participants consumed AG1 over a four-week period, while the rest received a placebo.

Throughout the study, researchers collected stool samples from the participants and conducted surveys about their digestive health.

The results indicated that those consuming AG1 showed modest improvements in their gut microbiome, the body’s ecosystem of beneficial bacteria essential for metabolism, immune support, and digestion.

There were also no negative effects, but the improvements were not statistically significant over people taking the placebo, meaning longer term research is needed to determine exact benefits.

Johnson instead pointed toward two cheaper supplements: chicory inulin and resistant starch, both of which are believed to improve gut health, balance blood sugar and maintain weight, though studies only show associations rather than proven benefits.

Biohacker Bryan Johnson (pictured here) slammed AG1 supplements over claims they are costly and minimally effective

F1 star Lewis Hamilton is pictured carrying an AG1 drink. He is an investor and has voiced his support for the brand

AG1 powder costs $79 per month with a subscription and $99 for a one-time purchase. Each bag has 30 servings. Chicory inulin powder ranges from $13 to $25 for a 16-ounce container, while resistant starch powder is around $20 to $40 for the same amount, which can last for roughly a month.

This adds up to $2.60 to $3.30 per serving of AG1 and between $0.40 and $1.33 for the alternatives.

Johnson said on X: ‘I’d cancel your AG1 subscription. They just completed a clinical trial and the results show no clinical benefit. This has been obvious for years. AG1 has no real product substance and is fundamentally an influencer heist. 

‘AG1 is not worth $79 [per month].’

On X, AG1 responded to Johnson’s post Wednesday and said ‘this year-old study doesn’t say what you’re claiming. It showed improved nutrient status and digestive quality of life, consistent with multiple randomized, placebo-controlled AG1 trials. Data > narratives.’

In a separate reply on X Wednesday the brand said: ‘Contrary to your false claims, our research program includes multiple clinical trials that demonstrate positive impacts. We believe in transparency and stand by the quality and results of our research.’

Daily Mail has reached out to AG1 for comment. 

Hugh Jackman is pictured in an ad for AG1. He claims he has been a customer since 2021

The clinical trial Johnson referenced was published in the Journal of the International Society of Sports Nutrition in 2024. It included 15 men and 15 women between ages 18 and 50 who filled out questionnaires about their digestive health, sent in stool samples before and after and underwent blood work.

The study found AG1 increased the amount of several beneficial probiotic species, including Lactobacillus acidophilus, Bifidobacterium bifidum, Lactococcus lactis and Acetatifactor sp. 

The team said that while it ‘appeared to be safe for daily consumption,’ the results were not statistically significant, and ‘further investigation of AG1 in a population with GI issues could potentially have a more significant impact on digestive quality of life based on these findings.’ 

The clinical trial was the most recently published one on AG1. The brand points on its website to that trial and several earlier studies to support its claims that the supplement boosts digestion, immune health, energy and gut health.

Johnson pointed to chicory inulin and resistant starch as alternative supplements to improve gut health. 

AG1 (pictured above), a greens powder that claims to support digestive and immune health, did not have significant benefits in a 2024 clinical trial

The above bar charts show diversity of bacteria in the participants’ stool samples before and after starting four-week AG1 supplementation compared to a placebo. The difference was minimal

Chicory inulin is a natural soluble fiber, meaning it dissolves in water to form a gel-like substance during digestion, helping to slow digestion down and promote fullness. It can be found in several foods, including asparagus, bananas, garlic, artichokes, leeks and onions, though it is also sold in supplement form.

Studies suggest chicory inulin helps support regular bowel movements and blood sugar control. One four-week study in 44 adults with constipation found taking 12 grams (0.4 ounces) of chicory inulin each day had softer, easier to pass stools and more bowel movements compared to a placebo. 

Another small study suggested taking 10 grams (0.3 ounces) per day increased the number of bowel movements from four to five. 

Resistant starch is a form of carbohydrate that resists digestion in the small intestine and instead ferments in the large intestine, feeding healthy bacteria, regulating blood sugar and increasing fullness.

A 2022 review found that resistant starch may improve insulin sensitivity and fullness but cautioned that it ‘is not a well-studied and documented component of the diet.’

Higher doses of either supplement can lead to bloating, abdominal pain, loose stools and gas.