Why aren’t vaccines tested against placebos?

Dr. Eric Berg, DC, says people don’t realize vaccines are toxic because they are tested against other vaccines. So why aren’t they tested against saline placebos?

• Vaccine studies can use saline, another vaccine, or certain ingredients for comparison. The choice depends on the question and how to protect participants.
• An ingredient’s safety depends on its amount and how the body handles it—not just its name.
• Vaccines saved an estimated 154 million lives over 50 years. They can cause side effects, but serious reactions are rare, and vaccines prevent far more harm than they cause.

A placebo is something used in a study to help scientists compare results. Many people think a placebo must always be saline, or salt water, but that is not true.

There are several kinds of comparison groups in vaccine studies. One uses an inert placebo, such as saline, which has no active ingredients. Another uses an active control, such as a vaccine that already works. Some comparisons use certain vaccine ingredients without the part that teaches the body to recognize the germ. These different comparisons help scientists answer different questions.

Scientists choose the comparison based on what they need to learn and how to protect the people taking part. A saline placebo can be used when there is no vaccine that already works. But if a safe and effective vaccine already exists, giving some people only saline may be unethical. It could leave them unprotected from a serious disease.

Giving protection is especially important for babies and children. If scientists already know a vaccine can prevent serious illness, they do not want to leave some children unprotected just to use saline in a study.

The pneumococcal vaccine is a good example. Prevnar-13 was tested against Prevnar-7, an older vaccine that already worked. If researchers had used saline instead, some children would have been left unprotected from dangerous bacterial infections. That could have put them at risk of serious illness or death. Comparing the new vaccine with the older vaccine helped scientists assess its safety and protection while still protecting children against the bacteria covered by Prevnar-7.

Both inert placebos and active controls are accepted in science. These studies help answer two main questions: Is the vaccine safe? And does it protect people from disease? No single comparison can answer every safety question, so safety checks continue after vaccines become available.

What about the ingredients used in an active control trial? An ingredient’s name alone does not tell us whether it is harmful. For vaccine ingredients, we consider the amount, how they enter the body, and how the body handles them.

We can also look at the bigger picture: how much harm vaccines prevent compared with the harm they can cause. Between 1974 and 2024, vaccination against 14 diseases saved an estimated 154 million lives worldwide. Vaccines also prevent illnesses that can cause paralysis, brain damage, and other lasting problems.

Vaccines can cause side effects, too. Most are mild, like a sore arm or fever. Serious reactions are rare, and the risks depend on the vaccine and the person. For example, a severe allergic reaction happens after roughly 1–10 out of every million vaccine doses, depending on the vaccine.

And many vaccines have also been tested with inert placebos, including those for rubella, pneumococcal disease, Hib disease, HPV, polio, measles, Tdap, and COVID. The key is choosing a comparison that answers the question while protecting the people who take part.