With the Affordable Care Act’s new enrollment period starting on Nov. 15, and then, for many, the activation of new insurance coverage on Jan. 1, we’ll be witnessing an intense period of “churn.”

Churn is the term often used to describe people moving back and forth between health insurance plans, e.g., between eligibility for Medicaid and eligibility for federal subsidies for private insurance bought on the ACA’s exchanges.

Such eligibility hinges on your income, which can change from year to year. Also, the subsidies themselves can fluctuate if your income changes by as little as one dollar. Suddenly you’re in a new bracket.

There are other scenarios, too. People with employer-sponsored insurance may now be required to join a high-deductible plan. Still others may have their hours cut so that they lose eligibility for job-based coverage altogether, throwing them on to the individual market.

Yet others may decide to change plans in search of lower premiums, deductibles, or co-pays. Or perhaps they want to follow a doctor who has left their plan’s network.

How many people are we talking about? Writing in Health Affairs in 2011, researchers estimated 28 million adults are subject to health insurance churn annually.

But churn can also be used more broadly to describe any disruption in coverage, doctors, hospitals, or access, whether initiated by enrollees or forced on them by employers or insurers.

Churn is an expensive, intricate process. It requires the work of thousands of people, the creation of new branches of specialized knowledge and new software, and the expenditure of millions of dollars every year to track and make adjustments for such changes.

Churn is frustrating for nurses and doctors, and it adds to our health system’s outrageously high administrative costs. We’re told we’re entering a new era of coordination of care, yet churn makes coordination impossible.

Churn is harmful to patients, and it is most harmful to the sickest patients. Loss of continuity of any aspect of access or care means that appointments are canceled, test results are lost, critical procedures don’t get done, prescriptions don’t get filled, and difficult decisions have to be revisited. It can result in preventable complications and even premature death.

Our private-insurance-based system is extremely complex. A recent Kaiser Family Foundation report notes that in the first year of the ACA’s exchanges, “assister programs” employed more than 28,000 full-time-equivalent staff and volunteers to help people navigate the health insurance maze. Even people with extensive experience of the health care system are bewildered by the complex trade-offs they face.

The Kaiser report also makes clear that the need for assisters continues long-term. It recommends funding for “different models for specialized assister expertise,” in, for instance, tax, family, and immigration law. It proposes development of “norms of professional practice for Marketplace assisters,” a national assistance information center, and “prototype information management systems.”

Yet all of this added bureaucracy doesn't necessarily give people access to affordable, high-quality care. It only gets some of them - for some will still fall through the cracks - some kind of health insurance that may well turn out to have high deductibles and co-pays that deter them from seeking care they truly need. And those who do seek care may find themselves in severe financial distress as a result.

Shouldn't we be providing all necessary health care to everyone, with a minimum of time and money devoted to bureaucracy?

I believe the answer is clearly yes—and that we have an effective model in front of our noses.

By using the Medicare program as a foundation and improving upon its existing benefits, we could quickly cover everyone—of all ages—in the country.

Researchers have shown that by eliminating costly private-insurance-related overhead and redirecting those savings into clinical care, we could assure that everyone has coverage for all necessary care, free choice of doctor and hospital, and no more co-pays and deductibles - for no more than our nation is spending now. Ninety-five percent of households would end up spending less.

The “single-payer” program’s buying clout would also rein in health spending.

And there would be no more churn: Once you’re in the Medicare for All program (i.e. when you’re born), you’d be covered for life. End of story.

We know the path to providing high-quality care while enhancing everyone’s financial security. It’s called an improved Medicare for All.

Let’s get it done.