Health care costs could drain your Social Security benefits in retirement, especially if you're a woman.

The average woman could spend an estimated 70 percent of her retirement check on health care costs, according to a recent study by the Nationwide Retirement Institute. The average man fares better, but still uses nearly half of his benefits to cover medical expenses.

Here's how the Nationwide analysis reached its disturbing estimates: It assumed a woman with a life expectancy of 88 married a man who would live to 85 and they both claimed Social Security at 62, which is the earliest and most popular age to file for retirement benefits, regardless of gender.

More than half of elderly married couples and nearly 75 percent single retirees depend on Social Security for the majority of their income in retirement.

"Women disproportionately rely on Social Security in retirement," said Nancy Altman, co-director of Social Security Works, which advocates for the expansion of the program. In fact, roughly two-thirds of Social Security beneficiaries age 85 and older are women.

In the Nationwide's bleak scenario, the man collects a monthly benefit of $1,543 and the woman collects $1,171 per month. (The average monthly benefit for a retired worker is $1,350, according to the Social Security Administration.)

Nationwide projects hefty health costs for the hypothetical couple.The man would pay $214,278 in medical costs in retirement and the woman would pay more than $289,682, because of her longer lifespan. The forecast includes what the couple would have to spend on long-term care at a nursing home or in an assisted living center.

Though medical costs often greatly increase toward the end of life, the expenses average out to $776 per month for a man and $928 per month for a woman in Nationwide's estimates.

By comparison, Fidelity Investments estimates a 65-year-old couple retiring in 2016 will need $260,000 to cover health care expenses and $130,000 to pay for long-term care for a total retiree medical cost of $390,000.

No matter what your exact health care costs are in retirement, you can take steps now to reduce them:

If you are in good health, the easiest way to keep health care costs from devouring your benefits is to wait to take Social Security.

If you claim at 62, your benefit would be about 25 percent lower than it would be at your full retirement age, which varies from 66 to 67 depending on when you are born, for the rest of your life. Most people claim before that age. (See chart below.)

Wait beyond your full retirement age and your benefit grows by roughly 8 percent each year until age 70. Put another way, it means that waiting until from age 62 to age 70 could increase your benefits by 76 percent.

"Women frequently claim Social Security early when their older spouses retire instead of waiting to maximize their benefits," said Roberta Eckert, vice president of the Nationwide Retirement Institute.

Health savings accounts offer three major tax benefits for retirement savers. The contributions are tax deductible and grow tax-free. Plus, account withdrawals are tax-free too if used for qualified medical costs.

The downside is that you have to use a high-deductible plan to get access to an HSA and you may have to tap the account to pay health costs before retirement.

You can contribute up to $3,350 to the HSA in 2016 if you have individual coverage, or $6,750 for family plans. You can add a catch-up contribution of $1,000 if you are at least 55.

When you collect Social Security, your Medicare Part B premiums, which pays for medical insurance if you are 65 or older, is automatically deducted from your benefits. In 2016, most people pay a $104.90 per month for Part B, but people with incomes above $85,000 for individuals and $170,000 for couples have higher premiums.

Medicare Part D, the drug coverage, can be deducted from your Social Security benefits too. The standard monthly premium is $34.10, but individuals with income above $85,000 and couple with income of $170,000 pay more as well.

Medicare doesn't cover everything. Part B pays only 80 percent of covered expenses, leaving you to pay the other 20 percent, with no cap on your maximum out-of-pocket spending.

Seniors often use Medicare Advantage and Medigap plans to handle those expenses.

"Use an insurance broker to help weed through all of the plans to find one that fits your needs at the best price," said Kristin Sullivan, a certified financial planner in Denver. "Shop around for better pricing during open enrollment in the fourth quarter."

The health care system is so complex for retirees that many financial advisors recommend their clients turn to experts for help if they can afford it.

"One of the best ways for retired clients to save on health care costs during retirement is to use the services of a health care advocate as well as a personal insurance bill payer specialist," said Mark LaSpisa, a certified financial planner with Vermillion Financial in South Barrington, Illinois.

A health care advocate is trained to help people avoid unnecessary medical costs, but their services can run as high as $300 per hour.

Billing specialists, which can cost up to $200 per hour or take up to 35 percent of any savings they find, dig into the minutia of medical invoices to make sure you were not overcharged and don't pay anything that should be covered by your insurance.

If all that sounds too pricey, prevention may be better than a cure.

"Keep yourself as fit and healthy as possibly by eating right and doing moderate exercise every day," said Kathryn Hauer, a certified financial planner with Wilson David Investment Advisors in Aiken, S.C. "Unavoidable health crises can hit hard, but the fitter you are, the better you will be able to weather them."

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