Calendar: April 5-11

Tomorrow
AS THE PLANET WARMS
More than 25 years ago, an MIT researcher chaired the National Academy of Sciences' first panel on climate change. In the years since, scientists across the world have amassed convincing evidence that global warming is real -- and soon could have devastating effects on the Earth and its inhabitants. But US politicians have been slow to take action on the scientific findings, choosing not to join international collaborations like the Kyoto Protocol. James Gustave Speth, founder of the World Resources Institute, an environmental group, will explain the schism between US environmental policies and those of other advanced nations, weigh the potential ecological consequences, and ask what citizens can do. ''Some Say By Fire: Climate Change and the American Response." MIT, Wong Auditorium, 70 Memorial Drive, Cambridge. At 3 p.m. For more information, go to http://lfee.mit.edu/calendar/ or call 617-258-5402.

FOOD AND FITNESS: POWERFUL MEDICINE?
Obesity, high blood pressure, and diabetes are the ''epidemics" of the moment, serious diseases that seem to be spreading like wildfire among people of all ages, economic backgrounds, and gender. But simple preventive tools don't require years of medical school or a prescription -- better nutrition and exercise can improve everything from mood to cholesterol levels. A panel of physicians will give a 90-minute lecture on how food and fitness can be powerful prevention as part of its ''Mini Med School" public lecture series. ''Nutrition & Preventive Medicine: Facts on Food & Fitness." New Research Building, 77 Avenue Louis Pasteur, Boston. From 5:30 to 7 p.m. Free, but registration required at www.hms.harvard.edu/longwood_seminars, or by calling 617-432-3038.

Thursday, April 7
RECOLONIZING EXHIBITS
For hundreds of years, the people who colonized, conquered, and decimated Native Americans have been the ones who wrote the history books and put together the museum exhibits. At the new National Museum of the American Indian, which opened this fall in Washington, Native Americans were asked to tell the history and design the exhibits. Curator Jolene Rickard will explain how the museum developed, giving insight into exhibitions like the ''Wall of Gold," hundreds of golden figurines that explain historical events from a Native American point of view, and the ''Our Lives" gallery, half of which was designed by curators and half by American Indians in North and South America. ''Historic and Contemporary Imaginaries of Indigenous America at the National Museum of the American Indian," Peabody Museum, 11 Divinity Ave., Cambridge. At 5:30 p.m. Free. For more information, call 617-496-1027.

FENDING OFF OLD AGE
The aching joints, fuzzy memory, and chronic fatigue that plague seniors may be a normal part of aging -- or signs of an underlying illness. One problem can feed into another: When illnesses like depression are mistaken for sadness, grief, or normal aging, they can go untreated, leaving a patient at risk for further medical and psychiatric problems. Dr. Cornelia Cremens, a geriatric psychiatrist from Harvard Medical School, will explain how to distinguish normal aging from the onset of debilitating diseases like dementia and Alzheimer's. ''Aging: Distinguishing Medical Illness, Psychiatric Illness, and Normal Aging," Massachusetts General Hospital, O'Keefe Auditorium, 55 Fruit St., Boston. Registration at 6:30 p.m., lecture at 7. Free, but preregistration is required. Call 617-724-8318, or e-mail info@moodandanxiety.org.

Saturday, April 9
HOW DOES BIG PHARMA AFFECT HEALTH AND HEALTHCARE?
With antidepressants linked to suicide and the popular anti-inflammatory Vioxx pulled from the market because of cardiovascular complications, critics are beginning to wonder how big pharma's cures affect patient health -- and the healthcare system itself. During a three-hour seminar, Jerry Avorn, a critic of the Food and Drug Administration; Phil Hilts, author of a recent history of the FDA; and Kenneth Kaitin, director of the Tufts Center for the Study of Drug Development, will discuss and debate the impact pharmaceutical companies are having on the future of medicine.
''Pharmaceutical Industry: The Critical Policy Questions for Health and Healthcare," Tufts University Boston campus, Sackler B Auditorium, 145 Harrison Ave., Boston. From 9 a.m. to noon. Free, but RSVP required to nkemdiri.iruka@tufts.edu.

Event notices may be sent to healthscience@globe.com.