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White blood cell

White blood cells (also called leukocytes or immune cells) are cells which form a component of the blood. They help to defend the body against infectious disease and foreign materials as part of the immune system. There are normally between 4x109 and 11x109 white blood cells in a litre of healthy adult blood - about 7,000 to 25,000 white blood cells per drop. In conditions such as leukaemia this may rise to as many as 50,000 white blood cells in a single drop of blood. As well as in the blood, white cells are also found in large numbers in the lymphatic system, the spleen, and in other body tissues.

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Health & Medicine News

August 10, 2026

An experimental GLP-1 pill helped people with obesity or overweight lose as much as 12.1% of their body weight in just 36 weeks. Unlike injectable drugs such as Wegovy and Ozempic, aleniglipron is a small molecule that can be taken once daily with ...
Very high levels of the inherited cholesterol-related particle Lp(a) were linked to a greater risk of major cardiovascular events, particularly stroke and cardiovascular death, in a study of more than 20,000 people. Since elevated Lp(a) often flies ...
A daily glass of 100% fruit juice or a smoothie may help improve more than just fruit intake. In a small four-week trial, participants who added one to a healthier diet showed significantly lower depression scores, hinting that a simple dietary ...
Just a couple of hours of strength training each week could have surprisingly powerful effects on longevity. People who lifted weights for around 90 to 120 minutes weekly had a 13% lower risk of dying early, with especially large reductions in ...
Frequent cannabis users may wake up with unusually high levels of the stress hormone cortisol, suggesting their daily stress rhythms could be disrupted. Researchers say the finding raises questions ...
Full-fat dairy may be healthier than conventional advice has suggested. In a 12-week study, adults who ate three servings a day showed no meaningful increases in weight, body fat, cholesterol, or ...
A study tracking more than 340,000 adults for over a decade found that heavy drinking increased the risk of death regardless of beverage type. At lower levels, however, the picture became more surprising: beer, cider, and spirits were linked to ...
An intensive seven-day meditation retreat triggered striking changes across the brain and body, including shifts tied to neuroplasticity, immunity, metabolism, and natural pain relief. Participants also showed brain connectivity patterns resembling ...
Getting the recommended 150 minutes of moderate-to-vigorous exercise each week may offer only modest protection against heart attacks and strokes. A large study suggests that substantially greater benefits may require roughly 560 to 610 minutes a ...
A protein that evolved long before the human circulatory system may help unlock stronger cancer treatments. When C3 is produced inside tumors, it blocks immune-suppressing cells and gives immunotherapy a better chance to work. Researchers were even ...
Changing how much sweet-tasting food people eat may not change how much they crave or enjoy sweetness after all. In a six-month trial, researchers found that people assigned to high-, low-, or average-sweetness diets showed no meaningful differences ...
Teens who start using cannabis may experience slower growth in memory, attention, language, and processing speed. Their abilities often developed normally at first, then began leveling off while nonusers continued improving. THC appeared to be the ...

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