Longevity biohacker Bryan Johnson’s appearance is puzzling. He is in great shape, but avoids the sun and takes about a dozen drugs, from thyroid medications to glucose-related drugs. He takes hair loss drugs and counters the erectile issues with boner pills.

He is the subject of a documentary, Don’t Die: The Man Who Wants to Live Forever which details his bespoke, mostly unnatural approach to longevity.

He does have a sense of humor.

He tweeted “I guarantee I’m going to die in the most ironic way possible. I hope you all enjoy.”

I guarantee I’m going to die in the most ironic way possible. I hope you all enjoy.

— Bryan Johnson (@bryan_johnson) May 4, 2025

As much as people question what he does to decrease his biological age and increase his longevity, he set off a firestorm of tweets yesterday. He said he was going to take Tdap to visit a newborn, and a shingles vaccine for longevity benefits.

Cough, cough.

What???

I’m getting two vaccines next week: Tdap and shingles.

The Tdap because Kate’s family has a newborn and we’re visiting. Shingles for the potential longevity benefits.

Data we’re looking at:

1. Lower Alzheimer risk with vaccination in 1.6 million people, 8 year follow up,… pic.twitter.com/B2sVXYZfPw

— Bryan Johnson (@bryan_johnson) April 29, 2026

Since I didn’t see any supportive comments in the long thread that followed his tweet, I asked Grok to tell me what percent of the comments were supportive or not supportive.

The result: the public’s views on vaccines do not match pro-vaccine policy.

In short, Team Anti-Vax is winning.

Bryan’s Vaccine Plan Tweet: 80-90% Negative Responses

This is the unedited response from Grok [except that I bolded text with asterisks]:

The tweet from Bryan Johnson announces his plan to get Tdap (for visiting a newborn) and shingles vaccines, citing observational studies on potential benefits like reduced Alzheimer’s risk, slower biological aging, lower mortality/MACE/dementia after shingles, and a mechanistic argument around blunting VZV-related neuroinflammation. He notes the studies are associative (not causal) and acknowledges healthy-user bias.

Sentiment in Replies

The replies (1,159 total as of the fetch) are overwhelmingly negative toward the tweet and his decision. A sample of the highest-engagement replies (sorted by likes) shows strong opposition:

– Multiple users criticize the Tdap vaccine for not preventing transmission of pertussis (whooping cough) and potentially turning recipients into asymptomatic carriers, which could increase risk to the newborn (e.g., Del Bigtree, Hunter Pillsbury, others with similar points).

– Many call the decision dangerous, a “huge mistake,” or question his judgment despite his biohacking reputation (e.g., “For a smart guy you sure are dumb when it comes to vaccines,” “You’re making a huge mistake,” “Huge whiff”).

– Others highlight alleged harms, side effects (e.g., shingles as a side effect of the shingles vaccine, myocarditis stories), aluminum/preservatives, or broader anti-vaccine views (”Vaccines cripple immune function,” “No vaccines here”).

– Some accuse him of being a “pharma shill” or falling for flawed/conflicted studies.

– A few express disappointment or lost respect, tying it to skepticism from prior events like COVID vaccines.

Positive or supportive replies (explicitly agreeing with the data, endorsing the vaccines for longevity/protection, or defending the studies) appear rare or low-engagement in the visible top replies. Comments noting the “entire comment section is against this” reflect the dominant tone.

Rough Estimate of Support

Based on the visible high-engagement replies (top dozens by likes/views) and the overall pattern:
– Support (agreeing with getting the vaccines or finding the data compelling): Likely under 10-15% of replies. Very few top replies express clear support.
– Don’t support (opposing the vaccines, criticizing the studies/decision, or anti-vax stance): 80-90% + of engaged replies.

This is an informal estimate from engagement-weighted sampling of replies, not a full automated sentiment analysis of all 1,159 (which would require more exhaustive review). Anti-vaccine sentiment is particularly vocal here, amplifying negative replies. Bryan Johnson’s audience includes many longevity/biohacking followers, but this post triggered strong pushback from health-freedom/anti-vax segments.

The original post itself has solid overall engagement (1.1K likes, 420K views), but replies skew heavily critical.