Vitamin D: Over the past decade, dozens of studies have revealed many important roles for vitamin D, the nutrient that skin cells produce when they are exposed to sunlight. The recommended daily intake of Vitamin D is 600 IU per day, although recommended levels are under review. If you avoid the sun or live in the northern half of the U.S., ask your doctor whether your vitamin D level should be tested.
Popular belief says if you really want to make a big change, focus on one new healthy habit at a time. But Stanford University School of Medicine researchers say working on your diet and fitness simultaneously may put the odds of reaching both goals more in your favor. They followed four groups of people: The first zoned in on their diets before adding exercise months later, the second did the opposite, the third focused on both at once, and the last made no changes. Those who doubled up were most likely to work out 150 minutes a week and get up to nine servings of fruits and veggies daily while keeping their calories from saturated fat at 10 percent or less of their total intake.
A workout partner not only keeps you accountable, she also may help you clock more time at the gym and torch more fat. A British survey of 1,000 women found that those who exercise with others tend to train six minutes longer and burn an extra 41 calories per session compared to solo fitness fanatics. [Tweet this fact!] Women with Bikram buddies and CrossFit comrades said they push themselves harder and are more motivated than when they hit the gym alone.
Fluids: Fluid needs increase as women age. The reason: Kidneys become less efficient at removing toxins. “Drinking more fluids helps kidneys do their job,” Schwartz says. “Unfortunately, thirst signals often become impaired with age, so people are less likely to drink enough water and other fluids.” Rather than fret about how many glasses to drink, Frechman says, check the color of your urine. "It should be clear or very pale colored. If it becomes darker, you need more fluid.”