When Not to Experiment

Urgent first

If you or someone else is in immediate danger, call emergency services (911 in the US). In the US you can call 988, the Suicide & Crisis Lifeline, if you are in emotional distress. If a self-experiment is leaving you feeling faint, dizzy, with chest pain, a racing heart or confusion, stop and get medical help.

Why this page exists

"Self-experimenting" here means changing a habit, diet, schedule, exercise or tracking routine on yourself to see what happens. Some changes are low risk. For some people, even simple ones are not a good idea without clinical guidance. This page lists who should check first and why. It is information only, not medical advice, and it cannot tell you whether you personally should or should not do something.

Evidence labels used here: established, mixed, insufficient evidence, commentary.

Check with a clinician first if you

• Have a medical condition, take regular medicines, or have not been active for some time. The NHS advises speaking to a doctor first before starting to exercise if you have not exercised for some time or have medical conditions or concerns. [1]
• Use insulin or other diabetes medicines, blood thinners, heart or blood pressure medicines, or psychiatric medicines. Do not change a prescribed medicine because of a tracker or experiment; ask your prescriber.
• Have a heart condition. Reviews describe health anxiety, alert-related worry and repeated reassurance seeking in some people with heart disease who use wearables. [2][3]
• Are pregnant or planning pregnancy. The NHS says exercise is safe in pregnancy, to start new exercise gently, and not to start a new vigorous activity such as running; people with an existing condition may need extra care and should speak to a midwife. [4]
• Are a child or teen, or are making decisions for one. The research we read focused on adults; we did not find evidence that heavy tracking or self-directed experiments are suitable for children.

Eating disorders and obsessive tracking

The NHS describes an eating disorder as a mental health condition where you use the control of food to cope with feelings and other situations, and lists very strict habits or routines around food and exercising too much among the symptoms. [5] The US National Institute of Mental Health says eating disorders are serious and can be life-threatening, and that they can be treated successfully. [6]

Does tracking cause eating disorders? Research is mixed:

• A meta-analysis of nine studies (13,507 adults) found no significant link between weight-related self-monitoring and eating disorder symptoms overall in the general population, and said individual factors likely decide who is affected. [7]


• A 10-day study of 262 women who had never used a fitness tracker found no significant effects on body satisfaction or exercise, and fewer binge-eating and dietary-restraint behaviors in the tracker group. [8]


• Among 105 people already diagnosed with an eating disorder, about 75% used a calorie-tracking app and 73% of those users perceived it as contributing to their eating disorder. [9]

Label: mixed. Tracking may not harm most people, but people who have or are in recovery from an eating disorder, or who feel driven to count and compare numbers, should not track food, weight or exercise without their care team. See Eating Disorders and Obsessive Tracking and Eating Disorders and Disordered Eating.

Sleep worry and insomnia

Clinicians have described patients who seek treatment for self-diagnosed sleep problems based on tracker data and a "perfectionistic quest for the ideal sleep". [10] If you have long-lasting trouble sleeping, see a clinician. Consumer sleep technologies cannot be used to diagnose or treat sleep disorders at this time. [11]

Other situations to avoid self-experiments

• Anything involving prescription-only drugs, injections, or unapproved compounds. This library does not give protocols for those.
• Extreme fasting, dehydration, breath-holding or intense heat or cold. This library does not give protocols for these and describes risks only.
• Experiments that would delay care for a new, worsening or frightening symptom.

Signs to stop and seek help

Stop and talk with a clinician if tracking or an experiment makes you more anxious, makes you avoid food or normal activity, disrupts your sleep, or if you feel unwell. For how to think about a careful experiment, see How to Evaluate a Biohack and Wellness Optimization vs Medical Treatment.