Quick answer You need some sodium, but most people eat far more than the recommended limit. The Dietary Guidelines recommend less than 2,300 mg of sodium a day, about 1 teaspoon of salt, while Americans average about 3,400 mg. Too much sodium raises blood pressure, which increases the risk of stroke and heart disease. Most…
Quick answer There is no single correct amount of water. A common guide is about 11.5 to 15.5 cups (2.7 to 3.7 liters) of total fluid a day for healthy adults, but needs vary with body size, activity, weather, and health. The “8 glasses a day” rule is an easy target, not a strict rule….
Quick answer Most adults do not get enough fiber. Recommendations are about 25 g a day for women and 38 g for men, dropping to about 21 g and 30 g after age 50. Fiber from food supports digestion, cholesterol, blood sugar, and weight, and is linked to a lower risk of heart disease, type…
Quick answer Creatine is one of the most studied sports supplements, and it works for a specific job: short bursts of high-intensity effort such as sprinting and weight lifting. It can increase strength and power, mainly when combined with training. It does not build endurance, and it adds some water weight. For healthy adults it…
Quick answer Most adults do not need a calcium supplement if they eat calcium-rich foods. The recommended intake is about 1,000 to 1,200 mg a day for adults, and dairy, fortified plant milks, tofu, leafy greens, canned fish with bones, and fortified cereals can cover it. Supplements are most useful for people who avoid dairy,…
Quick answer Most people do not need electrolyte supplements. A normal diet and ordinary water cover the electrolytes you lose day to day, because sodium and potassium are plentiful in food. Electrolyte drinks or powders can help when you sweat heavily for a long time, such as during hard exercise lasting more than an hour…
Quick answer Zinc may modestly shorten a cold if you start it within the first day or so of symptoms, usually as lozenges or syrup. The evidence is mixed and of low certainty, so it is not a reliable cure, and taking it after a cold is established does not seem to help. Zinc is…
Quick answer Most healthy people do not need an omega-3 pill. Eating fish twice a week, or using algae oil if you do not eat fish, covers the basics. Large trials of fish oil supplements have mostly not shown a clear benefit for preventing heart disease in people who are already healthy, though prescription-strength omega-3s…
Quick answer Most people who eat animal products get enough vitamin B12 from food and do not need a supplement. You are more likely to need one if you follow a vegan or vegetarian diet, are over 50, take metformin or long-term acid reducers, have had stomach or intestinal surgery, or have a condition like…
Quick answer For most people, taking vitamin C every day does not prevent colds. Large reviews of the research find that routine vitamin C does not lower the chance of catching a cold in the general population, although it may slightly shorten how long a cold lasts once you have one. A small group of…