Studies Link Sleep, Tea, and Cannabis to Heart Health Risks

Cannabis use associated with higher cardiovascular risk

Occasional cannabis use, defined as one to five days in the past month, is associated with a 23% higher likelihood of reporting a history of cardiovascular disease, according to the New York Post.

Cannabis use in the United States has reached historic highs, with as many as one in four adults using it within the last year. The odds of cardiovascular disease do not increase as marijuana use frequency rises, and researchers found no significant link between cannabis use frequency and heart attack.

Tea consumption linked to lower vascular disease risk

A study of 485,934 adults in China found that drinking six to eight cups of tea daily is associated with an 11% lower risk of combined vascular diseases. Researchers followed participants for a median of 9.05 years and recorded 14,863 cases of vascular diseases, including cardiovascular, cerebrovascular, pulmonary heart disease, and peripheral artery disease.

Drinking tea described as "burning hot" was associated with an increased risk.

Testosterone therapy may increase heart risks for women

Postmenopausal women using testosterone therapy may face a higher risk of stroke, heart attack, and other cardiovascular problems. Researchers observed more than 6,000 postmenopausal women aged 45 and older and found that 3.8% of those receiving the therapy experienced a first-time cardiovascular event.

This compares to 0.5% of women not receiving the treatment.

Researchers acknowledged that the study was observational and cannot prove causation, as participants may have differed in other health factors such as cholesterol, diabetes, blood pressure, or age.

Observational nature of health studies

Experts caution that many of these findings are observational, meaning they identify links between habits and health outcomes but cannot definitively prove causation. Researchers cannot establish that specific habits are responsible for the observed differences in health outcomes.

Study limitations include the inability to establish cause and effect due to the observational nature of the research and the use of wearable devices rather than standard lab-based brain monitoring.

Broader context of biological age and caffeine

A higher biological age is linked to a greater risk of mortality and disease, according to reporting from the Huffington Post on Oct. 30, 2026. 30, 2026. The same report found that a negative biological age gap may lower the risk of stroke and brain disease. Sleeping more or less than six to eight hours is associated with increased risks of all-cause mortality and systemic diseases.

A recent study tracked participants with an average age of 53, of which 69% were women. The group was 81.6% white, 4.6% Black, 3.1% Asian, and 10.7% other or unreported race.

She chaired the organization’s 2025 scientific statement, "Multidimensional Sleep Health: Definitions and Implications for Cardiometabolic Health". Video interview clips featuring St-Onge are available online. The American Heart Association is a 501(c)(3) tax-exempt organization that holds trademarks for "Red Dress," "Go Red for Women," and "National Wear Red Day".

Glazing on ceramic tea sets plays a role in retaining health-promoting flavonoids like catechins. A study of nearly 10,000 older women found tea consumption linked to higher hip bone density over 10 years. While moderate coffee consumption appears safe, heavy intake of more than five cups per day is associated with lower bone health.

An American Heart Association review determined that a daily caffeine intake of up to 400 milligrams is safe for the heart for most adults.