Background and career
Andrew Thomas Weil (; born June 8, 1942) is an American physician and author known for advocating integrative medicine, an approach that combines conventional medical treatment with selected complementary and alternative therapies. He founded the Arizona Center for Integrative Medicine at the University of Arizona College of Medicine in 1994. Weil has also written numerous popular books on health, healing, nutrition and ageing, several of which have appeared on bestseller lists. Weil studied biology and ethnobotany at Harvard University and received his medical degree from Harvard Medical School in 1968. His early interests included psychoactive drugs, medicinal plants and altered states of consciousness. After medical school, he conducted research on marijuana and other drugs at the National Institute of Mental Health, was affiliated with the Harvard Botanical Museum from 1971 to 1984, and travelled in Latin America and elsewhere studying medicinal plants and indigenous healing practices. His early books dealt largely with drugs and consciousness before his writing shifted toward health care and healthy lifestyles. Weil describes integrative medicine as combining conventional medicine with complementary approaches while emphasizing nutrition, exercise, stress reduction and the physician–patient relationship. He has promoted dietary supplements, herbal remedies, meditation and other practices alongside conventional treatment, and has been credited with helping to popularize integrative medicine. He also founded the restaurant chain True Food Kitchen and has developed other commercial ventures associated with his health recommendations. Weil's medical advice and commercial activities have attracted substantial criticism. Physicians and other critics have accused him of promoting treatments lacking adequate evidence and of disparaging aspects of evidence-based medicine. His business relationships and sales of supplements have also led to criticism over potential conflicts between his medical recommendations and commercial interests. In 2009, the Food and Drug Administration sent a warning letter to Weil Lifestyle LLC concerning the marketing of products in connection with the H1N1 influenza virus.
Weil was born in Philadelphia, on June 8, 1942, the only child of parents who operated a millinery store, in a family that was Reform Jewish. He graduated from Central High School (Philadelphia) in 1959, and was awarded a scholarship from the American Association for the United Nations, giving him the opportunity to go abroad for a year, during which he lived with families in India, Thailand, and Greece. From this experience, he became convinced that American culture and science was insular and unaware of non-American practices. He began hearing that mescaline enhanced creativity and produced visionary experiences, and finding little information on the subject, he read The Doors of Perception by Aldous Huxley. In 1960, Weil entered Harvard University, where he majored in biology with a concentration in ethnobotany. At Harvard, he developed curiosity about psychoactive drugs. He met Harvard psychologists Timothy Leary and Richard Alpert, and separately engaged in organized experimentation with mescaline. Weil wrote for Harvard Crimson. One published account of the period describes a falling out of Weil from the group that included the faculty—among whom the experimentation with drugs was contentious, and with regard to undergraduates, proscribed; the falling out involved an exposé on drug-use and supply that Weil wrote for the Crimson. Weil wrote of faculty experimentation with drugs in a series of Crimson pieces:
"Better Than a Damn" (February 20, 1962), his apparent first Crimson piece; "Alpert Defends Drugs on 'Open End'" (May 27, 1963); and "Investigation Unlikely in Dismissal of Alpert" (May 29, 1963). and that this reporting included the claim that "undergraduates had indeed been able to obtain access to psilocybin from members" of the Harvard faculty research team that was involved in such research. As late as 1973, Weil's name appears in conjunction with an editorial regarding the 1963 firing of Alpert, which stated the view that it would be "unfortunate if the firing of Richard Alpert led to the suppression of legitimate research into the effects of hallucinogenic compounds", distancing himself and the Crimson from the "shoddiness of their work as scientists ... less [the result] of incompetence than of a conscious rejection of scientific ways of looking at things". Weil's undergraduate thesis was titled "The Use of Nutmeg as a Psychotropic Agent", specifically, on the narcotic properties of nutmeg. In 1964, he graduated cum laude with a B.A. in biology.
Weil entered Harvard Medical School, "not with the intention of becoming a physician but rather simply to obtain a medical education". He received a medical degree in 1968, although "the Harvard faculty ... threatened to withhold it because of a controversial marijuana study Weil had helped conduct" in his final year. Weil moved to San Francisco and completed a one-year medical internship at Mount Zion Hospital in 1968–69. While there, he volunteered at the Haight-Ashbury Free Clinic. Weil went on to complete one year of a two-year program at NIH, resigning due to "official opposition to his work with marijuana."
Following his internship, Weil took a position with the National Institute of Mental Health (NIMH) that lasted approximately one year, to pursue his interests in research on marijuana and other drugs; during this time he may have received formal institutional permission to acquire marijuana for the research. Weil is reported to have experienced opposition to this line of inquiry at the NIMH, to have departed to his rural northern Virginia home (1971-1972), and to have begun his practices of vegetarianism, yoga, and meditation, and work on writing The Natural Mind (1972). At the same time, Weil began an affiliation with the Harvard Botanical Museum that would span from 1971 to 1984, where his work included duties as a research associate investigating "the properties of medicinal and psychoactive plants." His interests led him to explore the healing systems of indigenous people, and with this aim, Weil traveled throughout South America and other parts of the world, "collecting information about medicinal plants and healing," from 1971 to 1975, as a fellow for the Institute of Current World Affairs. In 1994, Weil founded the Arizona Center for Integrative Medicine at the University of Arizona College of Medicine in Tucson, Arizona. Andrew Weil is the founder of True Food Kitchen, a restaurant chain serving meals on the premise that food should make one feel better. There are currently 44 restaurants in the chain. Weil is credited with popularizing the 4-7-8 breathing technique.
Evidence-based medicine is a stated central component of the higher-order "system of systems" Weil envisions integrative medicine to be. It is clear that in both scholarly/academic and popular settings, Weil's statements suggest practices from alternative therapies as being something to add to conventional medical treatment plans. However, Weil is also on record speaking disparagingly of conventional, evidence-based medicine, both in academic and popular contexts. For instance, he is quoted as having said to a group commencing after a month-long training program in integrative medicine at the Arizona Center for Integrative Medicine that "that evidence-based medicine, at its worst, 'is exactly analogous to religious fundamentalism'" (though the source leaves unclear whether any specific aspect of evidence-based medicine was given).
Sources
Net-worth figure: Celebrity Net Worth (October 2026), in USD. Biography and career facts: the person's Wikipedia article and linked reporting. Snapshot date for all StarWorth figures: 28 October 2026.
