Reference Terms
from Wikipedia, the free encyclopedia
Calorie
A calorie is an unit of measurement for energy. The calorie was never a metric or SI unit. In most fields, it has been replaced by the joule, the SI unit of energy.
It remains, however, in common use for the amount of energy obtained from food. Recommended daily energy intake values for young adults are: 2500 kcal/d for men and 2000 kcal/d for women.
Nutritional calories are not measured amounts of energy, but are calculated from food composition. Such calculations use internationally agreed conventional conversion factors, which are generously rounded values that roughly approximate the average energy density of a large number of different food samples.
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Health & Medicine News
March 23, 2026
Mar. 23, 2026 Scientists have uncovered a hidden “death switch” in the brain that may be driving Alzheimer’s disease—and even found a way to turn it off in mice. The culprit is a toxic pairing of two proteins that, when combined, triggers the destruction ...
Mar. 23, 2026 A new blood test could change the outlook for one of the deadliest cancers—pancreatic cancer—by catching it much earlier than ever before. Researchers identified two previously unknown proteins in the blood that, when combined with existing ...
Mar. 23, 2026 A surprising new study reveals that blocking a supposedly protective enzyme, Caspase-2, could actually backfire—raising the risk of chronic liver damage and cancer over time. Researchers found that without this enzyme, liver cells grow abnormally ...
Mar. 22, 2026 Scientists have uncovered a surprising brain-based trigger for high blood pressure, tracing it to a small region in the brainstem that normally controls breathing. This area, which kicks in during forceful exhalations like coughing, laughing, or ...
Mar. 22, 2026 GLP-1 medications like semaglutide (Ozempic) may offer unexpected mental health benefits alongside weight loss. A large study found major drops in depression, anxiety, and psychiatric-related hospital visits among users. Even substance use disorders ...
Mar. 21, 2026 Antibiotics are accumulating in a major Brazilian river, especially during the dry season when pollution becomes more concentrated. Scientists even detected a banned drug inside fish sold for food, raising concerns about human exposure. A common ...
Mar. 21, 2026 A new pill, enlicitide, reduced LDL (“bad”) cholesterol by about 60% in a large clinical trial, matching the power of injectable therapies. Because it’s taken orally, it could overcome one of the biggest barriers keeping patients from using ...
Mar. 21, 2026 Researchers have discovered that cancer spread isn’t random—it follows a kind of biological “program.” By studying colon tumor cells, they identified gene patterns that signal whether a cancer is likely to metastasize. Their AI model, ...
Mar. 21, 2026 Scientists have engineered probiotic bacteria to act as tumor-seeking drug factories. In mice, these bacteria infiltrated tumors and produced a cancer-fighting drug right where it was needed. This targeted approach could make treatments more ...
Mar. 21, 2026 “Forever chemicals” may be affecting kids in ways that last a lifetime. A new study links early PFAS exposure to lower bone density during the teen years, especially in girls. Researchers also found that when exposure happens may play a key ...
Mar. 20, 2026 Aging men often lose the Y chromosome in a growing number of their cells—and it may be far more dangerous than once believed. This loss has been linked to heart disease, cancer, Alzheimer’s, and shorter lifespans. Researchers suspect Y-less ...
Mar. 20, 2026 The largest review of medicinal cannabis to date found it doesn’t effectively treat anxiety, depression, or PTSD—despite millions using it for those reasons. Researchers warn it could even make mental health worse, raising risks like psychosis ...
Latest Headlines
updated 12:56 pm ET
Mar. 20, 2026 A shingles vaccine might double as a powerful heart protector. In people already at high risk, it cut major cardiac events by 46% and deaths by an impressive 66% within a year. Scientists think ...
Mar. 20, 2026 Scientists have found a way to make one of the most aggressive brain tumors vulnerable to the immune system. A single injection of a modified virus can invade glioblastoma, kill cancer cells, and ...
Mar. 19, 2026 A common oral bacterium tied to gum disease may help spark and fuel breast cancer, according to new research. Scientists discovered it can travel through the bloodstream to breast tissue, where it ...
Mar. 19, 2026 Stopping popular weight-loss injections like Ozempic or Mounjaro might not trigger the dramatic rebound many fear. A large real-world study of nearly 8,000 patients found that most people who ...
Mar. 19, 2026 Eating large amounts of ultra-processed foods like chips, frozen meals, sugary drinks, and packaged snacks may significantly raise the risk of serious heart problems. In a major U.S. study, people ...
Mar. 19, 2026 Carrying extra fat around the waist may be more dangerous than the number on the scale suggests. Researchers found that belly fat was more strongly linked to heart failure risk than BMI, even in ...
Mar. 19, 2026 New strength training guidelines emphasize that doing any resistance training is what truly matters. Based on decades of research, experts say even simple routines can increase muscle, strength, and ...
Mar. 19, 2026 Malaria parasites contain tiny spinning crystals that have puzzled scientists for years. New research reveals they’re powered by a rocket-like reaction that breaks down hydrogen peroxide, releasing ...
Mar. 19, 2026 A new study suggests that eating less sweet food doesn’t make people crave it any less—or improve their health markers. Participants who increased or decreased sweetness in their diets showed no ...
Mar. 19, 2026 For years, people with prediabetes have been told the same thing: lose weight or risk developing diabetes. But new research flips that idea on its head, showing that blood sugar can return to normal ...