By definition, a placebo is an inert substance that has no effect on your body. In medical research, placebos (such as sugar pills) are used as controls against which the effects of drugs are measured.

However, the placebo-effect, in which a patient believes he or she is getting an actual drug and subsequently improves despite receiving no active substance at all, has become a well-recognized phenomenon.¹ Some studies into the placebo effect have even concluded that many conventional treatments “work” because of the placebo effect and little else.

Indeed, the placebo effect may even be at work in some surgical procedures, as evidenced in studies showing sham knee surgery is as effective as the real thing.^2,3This, despite the fact that the physical problem is in no way addressed.

Placebo Effect Works by Affecting Brain Chemistry and Circuitry

While we know the placebo effect is real, questions abound as to the mechanisms that makes it work. Writing in the journal Neuropsychopharmacology⁴ in 2011, the researchers highlighted the following observations:

1. First, as the placebo effect is basically a psychosocial context effect, these data indicate that different social stimuli, such as words and rituals of the therapeutic act, may change the chemistry and circuitry of the patient’s brain.

2. Second, the mechanisms that are activated by placebos are the same as those activated by drugs, which suggests a cognitive/affective interference with drug action.

3. Third, if prefrontal functioning is impaired, placebo responses are reduced or totally lacking, as occurs in dementia of the Alzheimer’s type.

As noted by The Washington Post and published studies,^5,6 researchers have also discovered a “hierarchy of effectiveness,” with certain types of placebos appearing to have stronger effects than others. For example, injections or creams have stronger placebo effects than pills, and sham injections and sham acupuncture (which also uses needles) being more effective than placebo pills.

Price also matters,⁷ with expensive pills or treatments garnering better results than inexpensive ones. Lastly, telling the patient that the treatment will relieve their symptoms produces a greater placebo effect than saying it “might” help.

Your Expectations Direct Your Body Chemistry

Using brain imaging technology during placebo tests, researchers have been able to show that even when a placebo is used, your brain still responds according to expectations.

For example, in trials involving placebos for pain relief, the participant’s brains release natural opioids that provide opioid-mediated pain control. So, the placebo effect is tapping into the same pain control centers as opioid drugs. Placebos can also trigger the release of many other natural brain chemicals, such as those involved in making us feel more energized, or those that help us sleep better.

In short, the placebo effect taps into your body’s own virtual pharmacy. Drugs work because your body has chemical receptors for the drugs, but you also have natural brain chemicals that act on those same receptors. This is why placebos so often can mimic the effects of the drugs.

This tells us that the placebo effect is not illusory. Rather, it relies on your body’s own chemicals, which are released in response to or in accordance with your mental or emotional expectations or beliefs. With that in mind, just how far can a placebo take you? Placebo trials on patients with Parkinson’s disease have revealed that even this serious condition can be ameliorated with a dummy pill.

Lack of dopamine is one of the factors producing the symptoms of Parkinson’s, and brain scans show that when Parkinson’s patients are told they’re receiving an active medication, the dopamine levels in their brains increase, even when there’s no active ingredient in the pill. Remarkably, a placebo can release as much dopamine as amphetamines in a person with a healthy dopamine system,⁸ so the response can be quite dramatic.