Harvard Health Content API

The glymphatic system serves as the brain’s cleanup crew. It promotes the circulation of cerebrospinal fluid through the brain during deep sleep, flushing away amyloid and other proteins that can lead to neurological conditions such as Alzheimer’s, Parkinson’s disease, and Lewy body dementia.

A 2026 study indicates a precipitous decline in the number of primary care providers in the United States accepting new patients. Without a primary care doctor, people are more vulnerable to serious medical problems and may have trouble getting regular tests and prescriptions.

Pregnancy complications such as gestational diabetes and preeclampsia—marked by high blood pressure that can impair organ function and affect blood vessels—are increasingly tied to higher lifetime cardiovascular risks. Women with these complications face greater odds of heart attack, stroke, and diabetes.

Revenge bedtime procrastination involves sacrificing sleep to prioritize personal time for activities unrelated to the demands of work or caregiving. Short-term effects of insufficient quality sleep time include next-day fatigue and negative mood. Persistent sleep deprivation can increase risks of conditions such as cardiovascular disease and dementia.

Chemotherapy treatment in women can diminish hormone levels that affect sexual health and intimacy. It can also alter self-image, sex drive, and emotions. Research suggests anywhere from 40% to 100% of cancer survivors struggle with sexual dysfunction.

A 2026 study of people with carpal tunnel syndrome found that wearing a rigid wrist splint provided minimal improvement and did not improve symptoms better than wearing a soft bandage for 12 weeks. Rates of surgery within one year were also similar.

Achilles tendons can be injured in several ways. Overuse can irritate and inflame the tendon (tendinitis). Abrupt movements that stretch the tendon in the wrong way can tear the tendon (rupture). Nonsurgical treatment often is effective. Some cases may require surgery.

Muscles naturally weaken over time. But people can preserve strength and retain function with regular physical activity, including exercises to build lower-body strength. Four daily exercises are sit‑to‑stands, glute sets, heel raises, and single‑leg stands.

Regular resistance training, with either home-based or gym exercises, improves strength, muscle size, power, endurance, and daily function. New guidelines recommend resistance training with high effort that works all major muscle groups at least twice a week.