Your Tap Water Could Be Affecting Your Heart

A new 13-year study of 324,000 adults reveals how magnesium and calcium levels in your tap water may subtly influence cardiovascular resilience[ri-zil-yuhns]nounThe ability to recover quickly from stress or setbacks.Learn MoreClose.

A quiet factor in heart health[hahrt helth]nounThe overall condition and function of the cardiovascular system, including blood pressure, cholesterol, and arterial health; critical for longevity and disease prevention.Learn MoreClose may be hiding in your kitchen tap. A massive new study published in The American Journal of Clinical Nutrition of more than 324,000 adults followed for over 13 years to explore how the minerals in tap water, specifically magnesium (Mg), calcium (Ca), and calcium carbonate (CaCO₃), affect cardiovascular health.

The Surprising Link Between Water Hardness and Heart Health

The results reveal a subtle but important pattern. Higher magnesium levels were linked to a lower risk of cardiovascular disease (CVD), while calcium and overall water hardness followed a U-shaped curve: moderate levels were associated with better outcomes, but very low or very high concentrations weren’t ideal. In fact, those exposed to extremely hard water, especially with high calcium content, showed a slightly higher risk for certain heart conditions like rheumatic heart disease[hahrt dih-zeez]nounConditions affecting heart health and circulation.Learn MoreClose.

This is another reminder that small environmental exposures, like the mineral balance in our water, add up over time. Magnesium appears to support heart rhythm, reduce inflammation[in-fluh-mey-shuhn]nounYour body’s response to an illness, injury or something that doesn’t belong in your body (like germs or toxic chemicals).Learn MoreClose, and help regulate blood pressure, while moderate calcium levels may strengthen vascular tone. The lesson isn’t to overhaul your plumbing, it’s to recognize that water quality is part of the long game of cardiovascular resilience.

6 Simple Takeaways

Extremely hard water, particularly high in calcium, was tied to a slightly higher risk of chronic rheumatic heart disease.

1. Check your water report

Most city or regional water suppliers post annual water quality data. Look for calcium, magnesium, and total hardness (listed as CaCO₃).

2. Aim for balance

Moderate hardness appears optimal. Too little mineral content (very soft water) or too much (very hard water) may shift your risk curve in the wrong direction.

3. Don’t fear minerals

Reverse osmosis and bottled waters are often low in magnesium. If you rely on them, consider a mineralized filter or add trace minerals back in.

4. Prioritize dietary magnesium.

Daily intake matters more than your tap. Eat leafy greens, beans, nuts, seeds, dark chocolate, and mineral-rich salts to reach the recommended 310-420 mg per day.

5. Keep calcium in check.

Calcium supports bone and vascular health, but excessive intake, especially through supplements, can backfire. Food sources like sardines, yogurt, or kale are ideal.

6. Stay focused on the fundamentals.

Water hardness is one small piece of your longevity[lon-jev-i-tee]nounLiving a long life; influenced by genetics, environment, and lifestyle.Learn MoreClose mosaic. Regular exercise, strong social ties, good sleep, and stress management remain the foundation of heart health.

Bottom Line

The minerals flowing through your pipes are shaping your biology, quietly and continuously. Magnesium stands out as a longevity mineral, buffering stress at the cellular level and tuning the body’s electrical rhythm. The message is simple: your environment is part of your healthspan[helth-span]nounThe number of years you live in good health, free from chronic illness or disability.Learn MoreClose equation. Pay attention to the inputs you can measure; sometimes, longevity starts with what’s in your glass.

The Best Water Filters and Remineralizers 

1) First, Test Your Tap Water:

The Environmental Working Group (EWG) offers a free Tap Water Database where you can easily check the safety of your local water supply by entering your ZIP code.

2) Then, Filter Your Water. Here are the best water filters:

For cleaner, healthier water, consider using a high-quality filter. Prioritize options tested for contaminant removal, such as:

• Best Straw Filter: LifeStraw Home Water Filter Pitcher: Reduces lead, mercury, and “forever chemicals,” and pesticides.

• Best Faucet Filter: PUR Plus Faucet Filtration System: Certified by the Water Quality Association to remove over 70 contaminants.

• Best Countertop Filter: Rorra Countertop System: Removes lead, forever chemicals, microplastics, and 50+ other contaminants.

• Best Under Sink Filter: Aquasana Under Sink Water Filter System:Reduces PFAS, microplastics, lead, and chlorine

• Best Shower Filter: AquaBliss Revitalizing Shower Filter: Reduces chlorine, chlorine byproducts, and pesticides.

• Best RO Filter: Home Master Artesian Reverse Osmosis System: Removes up to 99% of contaminants, including chloramines, chlorine, and heavy metals. You can remineralize your RO water by adding a remineralization filter to your RO system, or by using an alkaline water filter pitcher, or even simply adding Pink Himalayan Sea salt to your water. 

Stay proactive, stay informed, and stay hydrated, on your terms.

Read This Next