You may assume that if your weight is in the healthy range, you have a low risk of heart disease, diabetes, and other conditions linked to obesity. But new research suggests that waist size could play as important a role as body weight in determining how long you live. After examining a database of more than 100,000 men and women ages 50 and older participating in a cancer prevention study, researchers found that those with the largest waistlines had about twice the risk of dying over a nine-year period as those with the smallest waistlines. (Nearly 20 percent of the men and 10 percent of the women died over the duration of the study, mainly from heart disease, cancer, and respiratory conditions.)

What's especially troubling, though, is that even big-waisted folks who had a healthy body mass index—a measurement of weight to height—had a higher risk of dying. Every 4-inch increase in waist size was associated with a 25 percent greater risk of death, says Eric Jacobs, an epidemiologist at the American Cancer Society who led the study, published in the Archives of Internal Medicine . What is an ideal waist size? Less than 35 inches for men and 30 inches for women, according to the study. These measurements are considerably smaller than what the American Heart Association defines as optimal: below 35 inches for women and 40 inches for men.

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Why is a big waist so dangerous? Previous research indicates that those who carry more fat around their abdomen also have higher amounts of fat around vital organs like the kidneys, liver, and pancreas; this so-called visceral fat is more "metabolically active" than fat that lies just below the skin and is thought to promote chronic inflammation, which has been linked to heart disease, diabetes, and certain cancers. Jacobs believes that action should be taken the moment you notice your pants getting too tight. "The take-home message is that it's important to watch your waist, not just your weight," he says, "and to start eating better and exercising more if you see your waist size starting to increase."

While eating fewer calories or burning off more through exercise can help reduce abdominal fat, a spate of recent studies also suggest that reducing stress and getting enough sleep—seven to eight hours a night for most people—can lower levels of stress hormones; that's a good thing since some of these hormones trigger the body to produce visceral fat. Researchers are also studying mindful eating, where you eat slowly and pay attention to the taste, smell, and texture of your food, to see whether the practice helps redistribute body fat from the waist to the hips.

Sure, we all know the basic nutrition rules when it comes to safeguarding our health and losing weight. In the words of best-selling nutrition writer Michael Pollan, "Eat food. Not too much. Mostly plants." Sounds simple, but if you're interested in maximizing the amount of nutrients you get, you may want to be a little choosy when selecting among various options in each food group. Some fruits, vegetables, grains, and dairy products stand out as nutritional superstars, according to the latest research. And they're also easy on the calorie count to help you shed pounds. Consider incorporating these foods into your daily meal plan.

A soda a day? That's not so bad—a 150-calorie blip, burned off with a brisk half-hour walk. But it's not only your waistline that's at stake. A study released today in the journal Diabetes Care found that people with a daily habit of just one or two sugar-sweetened beverages—anything from sodas and energy drinks to sweetened teas and vitamin water—were more than 25 percent likelier to develop type 2 diabetes than were similar individuals who had no more than one sugary drink per month. Since the overall rate of diabetes is roughly 1 in 10, an increase of 25 percent raises the risk to about 1 in 8. One-a-day guzzlers in the study also had a 20 percent higher rate of metabolic syndrome, a collection of indicators such as high triglyceride levels suggesting that diabetes is not far off.

"Previous studies have shown that sugar-sweetened beverages are strongly associated with weight gain," says lead author Vasanti Malik, a research fellow in the Harvard School of Public Health Department of Nutrition, who says the decision to examine the relationship between sugar-sweetened beverages and risk of diabetes was "the logical next step."

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The researchers conducted a study of studies—a meta-analysis—to reach their conclusions. They identified eight studies with enough data to let them check for a link between sugary drinks and type 2 diabetes and three similar studies of metabolic syndrome. The largest diabetes study, which followed more than 91,000 American women ages 24 to 44 for eight years, made the strongest case for a relationship, and it wasn't just because higher consumption of sweetened drinks added excess calories that turned into pounds. While weight gain is a known diabetes risk factor, the diabetes-beverage link persisted even after adjusting for that. "Other factors independently put you at risk for developing diabetes," says Malik.

The main one is spikes in blood glucose and insulin because sweetened drinks are often consumed quickly and in large quantities and their sugar content is rapidly absorbed. Frequent spiking can lead to insulin resistance, inflammation, and hypertension—often precursors to diabetes. High-fructose corn syrup, the sugar in many sweetened drinks, is emerging as possibly riskier than other sugars because it seems to produce more belly fat. Fat that accumulates around the middle is closely tied to high blood pressure and other cardiovascular problems.

Americans love sweetened drinks. Consumption climbed to an average of 142 calories a day, or nearly one 12-ounce can of soda, in 2006, from 65 in the late 1970s. And many people down far more than that, notes Frank Hu, a senior author of the study and a professor of nutrition and epidemiology at Harvard, which puts them at a much greater risk of diabetes. A report from the Centers for Disease Control and Prevention released earlier this week projects that by 2050, 1 in 3 Americans will develop the disease. "Soft drink consumption has significant public health implications in terms of the diabetes epidemic," says Hu.

Earlier this year the American Heart Association issued a recommendation advising consumers to set a limit on sweetened drinks of 450 calories a week, or three 12-ounce sodas, in a 2,000-calorie diet. Calorie-counting is a convenient way to keep track, but it can be misleading. "Consumers are overly focused on calories," says Constance Brown-Riggs, a spokesperson for the American Dietetic Association, who would like people also to understand that a 12-ounce can of soda contains the equivalent of 15 teaspoons of sugar. "They think it's not that bad, without taking into consideration the other components that are putting them at risk."

Type 2 diabetes and metabolic syndrome aren't the only risks of a one-a-day habit. In a 2004 study published in the Journal of the American Medical Association of 88,000 women followed for 24 years, those who guzzled two or more sugary drinks a day had a risk of coronary artery disease 35 percent higher than non-guzzlers, even after adjusting for other unhealthy lifestyle factors. "You receive no benefits out of drinking these beverages," says Malik, who lists additional hazards from dental cavities to gout. "It's a wake-up call for the American public."

Choosing the right health coverage has never been easy, and the health reform law has made things more complicated—especially for those choosing among plans provided by their employer. Besides sorting through differences in premiums, deductibles, and copayments, you need to consider new provisions in the law that have recently kicked in and could impact your coverage for the coming year. The following tips can help clear away the confusion, and help you choose the right plan during the open enrollment season.

1. Check for grandfather exemptions. If your employer makes no substantial changes to your insurance plan, it may be "grandfathered in" and not subject to certain required provisions in the health reform law. These include free coverage (with no copay) for preventive services like blood pressure or depression screening, smoking cessation programs, and immunizations. Plan materials will indicate whether or not the plan is grandfathered, along with the benefits it provides.

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2. Decide which plan type best meets your needs. There are generally three types of plans: health maintenance organizations (HMO), preferred provider organizations (PPO) and point-of-service plans (POS). An HMO requires that you use physicians within a specific network, giving you less flexibility but a more affordable cost. A PPO allows you to stay in-network or go out of network for a heftier fee; out-of-pocket costs are usually higher for PPO's than for HMO's. POS plans combine elements of HMO's and PPO's. They give you the option to pay more for venturing out of network, but usually require you to choose a primary care physician within the network and get a referral from that physician before seeing any specialist.

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3. Identify changes before re-enrolling. That could save you from dealing with unexpected costs if your benefits have changed. Coverage for a particular service such as chiropractic care may have disappeared, or the cost of covering your spouse may have increased. So it could pay to change plans. More likely, your monthly premiums have gone up, due to rising healthcare costs.

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4. Make adjustments to your current plan or consider switching. Take into account whether your needs have changed. If you're planning a family, you might need maternity coverage, for example, or perhaps you'd like to add an adult child back onto your insurance. All plans are now required to cover children up to age 26, though grandfathered plans may exclude these young adults if they have access to health benefits through an employer. Adult children, like those under 18, can no longer be rejected for having pre-existing conditions like asthma or cancer.

5. Factor in your favorite doctors. Before electing a different plan, check to see that your primary care physician and specialists are in its provider network. Women in non-grandfathered plans now have the freedom to see an obstetrician-gynecologist without a referral, but they still need to make sure any doctor they choose participates in their plan's network if they have an HMO or don't want to face extra fees if their plan is a POS.

6. Size up the cost. Compare the total cost of various plans using an online calculator, a tool offered by many employers. If you are young and healthy, you may want to trade pricey monthly premiums for a higher deductible (paying more out-of-pocket before coverage starts). Be sure to factor in copays (the physicians' fees) and coinsurance (your share of the cost for prescriptions or hospitalization).

7. Don't get lured by those new freebies. While new plans now require you to pay nothing for certain routine preventive care, you might not need to switch off your old plan to reap this benefit. Many plans were already offering preventive services at minimal or even no cost prior to the passage of health reform, says Randall Abbott, a senior healthcare consultant with Towers Watson, a global consulting firm based in New York.

8. Consider opening an account for your healthcare expenses. To save on premiums, think about setting up a healthcare savings account to help pay for prescriptions, contact lenses, and other medical expenses. Contributions to a health savings or flexible spending account are subtracted from your pretax income— a big plus. There are, though, some drawbacks to both. A health savings account has to be paired with a high-deductible plan—with an annual deductible of more than $1,200 for an individual and even more for a family. While a flexible spending account can go with all plan types, you lose any leftover contributions that go unused at year's end. Beginning in January, you can no longer pay for over-the-counter medications, like Tylenol or Prilosec, using HSA or FSA dollars unless you get a written note from your doctor.

9. Check out the prescription coverage. Your plan may add or drop certain drugs that were covered the previous year, so make sure whatever pills you take on a regular basis are still covered this year. This information is included in a plan's listing of medications or formulary and may be available online. Find out if there are additional discounts on generic drugs and whether you have the option of saving more by receiving prescriptions by mail.

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10. Take advantage of wellness incentives. Companies often offer employees cash incentives to complete a lifestyle questionnaire that covers things like exercise and smoking habits. Employers use these assessments to encourage workers to participate in wellness activities such as fitness programs or smoking cessation to reverse bad habits and lower health premiums for the company and its employees.

11. Don't forget to reconcile your spouse's coverage with your own. If your spouse or kids are covered under your plan, make sure your employer is still contributing the same amount toward premiums for family plans. Some have begun charging for each dependent, which could make it too expensive to add that 22-year-old child back onto your plan. Employers are also increasingly adding surcharges for spouses whose companies offer insurance; you may find it's no longer cost effective to keep your spouse on your plan.

12. Plan for the worst. Experts advise employees worried about being laid off to consider a plan with a lower premium. Laid-off employees who continue coverage through COBRA now have to pick up the entire cost themselves, since a government subsidy that chipped in substantially ended last June.