Medically reviewed by Jackie Giannelli, FNP-BC, MSCP

Can tap water make you sick? If you live in the U.S., it’s unlikely, but possible, that your tap water can give you a stomach bug. But the real question in midlife is: what’s in your water, and what is it doing to your thyroid, your estrogen levels, and your bones over years?

There are real hormonal ramifications from drinking tap water repeatedly. And that cute pitcher you’ve got or your fridge’s water filter may not be enough to stop the exposure.

So let’s take a look at what’s actually in your water and what to do about it.

Want the shortcut? My free What’s In Your Water prompt reads your town’s water report for you and tells you, in plain English, whether a filter makes sense.

Can tap water make you sick?

Yes, tap water can make you sick, but in the U.S., getting something like a stomach bug from tap water is uncommon. The Centers for Disease Control and Prevention (CDC) says 9 out of 10 Americans get their tap water from a public water system, and that public tap water in the United States is usually safe to drink. (1)

Tap water can potentially make you sick in two very different ways:

1. Fast. Germs like E. coli, Giardia, or Cryptosporidium get into the supply after a main break, a flood, or a failing well. You feel it within days: nausea, cramps, diarrhea. Typically, when a situation like this arises, you’ll get a notification from your water supplier to boil your water before using it to brush your teeth or drink. Listen to them.
2. Slowly. Chemicals at low levels, sipped every day for years, can impact your body in ways you don’t feel immediately.

Things like PFAS (per- and polyfluoroalkyl substances, often called “forever chemicals”), nitrate, medicines, and lead can actually be present in tap water in small amounts. Repeated exposure, over time, can certainly cause trouble.

What tap water does to your hormones

Can tap water make you sick in a way that’s specific to perimenopause and menopause?

Yes, it can matter more in midlife, because three of the contaminants that show up most often in U.S. water act on systems that are already changing in your 40s and 50s: estrogen, thyroid, and bone.

PFAS and your estrogen

PFAS (“forever chemicals”) are a family of industrial chemicals used in nonstick, stain-resistant, and waterproof products, and they build up in the body over years. The Endocrine Society considers them endocrine-disrupting chemicals, meaning they can interfere with how hormones are made and signaled. (12)

If you want the basics of how hormone-mimicking chemicals work, read: what xenoestrogens actually are.

The finding that made me pay attention came from the Study of Women’s Health Across the Nation, a long-running American research project that has followed thousands of women through the menopause transition. In a group of 1,120 midlife women followed for 17 years, the women with the highest PFAS levels in their blood reached menopause about two years earlier than the women with the lowest. (2)

That study was observational, and there’s a real chicken-and-egg question in it: your period is one of the ways your body clears PFAS, so stopping earlier could raise your levels rather than the other way around. I’d call it a strong signal that still needs a clear mechanism.

Nitrate and your thyroid

Nitrate is a fertilizer and septic-system runoff chemical, and it’s most common in well water in farming areas. The EPA’s legal limit for nitrate is set to protect infants. For adults, the thyroid is the concern I watch: nitrate can compete with iodine at the thyroid gland, and iodine is what your thyroid needs to make its hormones.

In the Iowa Women’s Health Study, a large study of older women, researchers linked long-term exposure to higher nitrate in drinking water with thyroid problems. (4)

PFAS show up here too. In a CDC national health survey, women with the highest blood levels of PFOA were more likely to report being treated for thyroid disease. (5)

Why does that matter to you? Thyroid symptoms (fatigue, weight change, brain fog, feeling cold) overlap almost perfectly with perimenopause symptoms. So it’s worth tracking thyroid hormones along with your sex hormones to make sure you know for sure what’s causing your symptoms.

Lead, your bones and menopause

The CDC’s Agency for Toxic Substances and Disease Registry estimates that about 94% of the lead in an adult’s body is stored in bones and teeth, some of it from decades ago. (6) During menopause, bone breaks down faster as estrogen falls, and that stored lead moves back into your blood.

A nationally representative U.S. study of women aged 40 to 59 found that women after natural menopause had blood lead levels about 25% higher than women who hadn’t reached menopause yet, and lower bone density corresponded with higher blood lead. (7)

Why it matters: lead nudges blood pressure up, strains your kidneys, and is linked to memory changes with age, all things already on the move in menopause.

You can’t do much about the lead already in your bones. But you can make sure your tap isn’t adding more on top of it right when your body is releasing its own.

The EPA’s goal for lead in drinking water is zero, because there’s no known safe level. (8)

Medicines and hormones in your water

Trace amounts of medicines and hormones do show up in U.S. tap water. An Associated Press investigation found pharmaceuticals, including sex hormones, in the drinking water of 24 metropolitan areas serving at least 41 million Americans, and a 2009 national study of treated drinking water detected estrone, a form of estrogen, alongside drugs like carbamazepine and naproxen. (13, 14)

Here’s what happens. You take a medicine or oral contraceptive pill. Your body only uses part of each dose, and the rest goes down the drain, through a wastewater plant, and back into the rivers and lakes that towns downstream draw their drinking water from. Problem is, the water treatment plants aren’t designed to remove hormones or leftover prescription compounds from the water before it turns into tap water, although the World Health Organization estimates chlorination removes about half of them. (15)

The amounts are tiny. The World Health Organization found levels in treated water typically more than 1,000 times below the smallest therapeutic dose, and called appreciable harm to human health very unlikely. (15) There are no federal drinking-water limits for them.

Of everything in this section, this is the one I’d lose the least sleep over. PFAS and lead have much stronger evidence behind them for midlife women. The good news is that the fixes overlap: reverse osmosis removes more than 99% of larger drug molecules, and activated carbon reduces many of them too. (15)

How do I know what’s in my tap water?

To find out what’s in your tap water, start with the free information your utility already has to give you, then test only what the report can’t tell you. Here’s the order I’d follow:

1. Find your Consumer Confidence Report. Every community water system has to send customers an annual water quality report, usually by July 1. (9) Search “[your town] water quality report” or check your water bill. It lists what was detected and how that compares to the legal limit.
2. Look up your service line. Utilities were required to publish an inventory of lead service lines (the pipe from the street to your house) by October 2024. (8) Search “[your utility] lead service line inventory” and put in your address. If your line is listed as lead or “unknown,” that’s your cue to test.
3. Test your own tap if your house is older. The report tells you what left the treatment plant. Lead usually comes from the pipes and fixtures between the plant and your glass, so a home built before 1986 deserves its own lead test. Your utility or state health department can point you to a certified lab.
4. Check PFAS against the new limits. Many reports don’t yet lay PFAS numbers out in plain language. My free What’s In Your Water prompt does this part for you: tell it your town, and it reads your report against the current federal limits. In 2024, the U.S. Environmental Protection Agency (EPA) set the first enforceable limits for two PFAS, PFOA and PFOS, at 4 parts per trillion each. (3) If your water report shows either one above 4, that’s your cue to filter.

City water vs. well water: who is checking yours?

If you’re on city water, your utility tests it on a schedule and reports to you. If you’re on a private well, you’re the only one testing it.

The U.S. Geological Survey (USGS) estimates about 43 million people drink from private wells, which aren’t covered by the Safe Drinking Water Act, and when USGS scientists sampled 2,100 of them, about 23% had at least one contaminant at a level of potential health concern, most often radon, arsenic, uranium, manganese, or nitrate. (10)

I learned this one personally. When we tested the well at the house we just sold, it came back with slightly elevated uranium. Nothing about the water looked, smelled, or tasted different.

	City water	Private well
Who tests it	Your utility, on a federal schedule	You
What you get	An annual water quality report	Only what you pay a lab to test
Most common midlife concerns	PFAS, lead from older pipes, disinfection byproducts	Nitrate, arsenic, uranium, radon, bacteria
What to do	Read the report, check your service line, test for lead if your house is older	Test every year for bacteria and nitrate, and every few years for metals and PFAS

Do I need a water filter? Pitcher vs. under-sink carbon vs. reverse osmosis

You need a water filter if your report or your own test shows something above the limit, or if your house has lead pipes. Match the filter to what’s actually in your water, and check that it’s certified for that exact contaminant. For lead and for PFOA and PFOS, look for certification to NSF/ANSI Standard 53 or 58 on the specific contaminant, not just the brand name. (11)

	Pitcher filter	Under-sink carbon block	Reverse osmosis (RO)
Best for	Renters, small budgets, one person	Most city-water homes	PFAS above the limit, nitrate, well water
Lead	Some models are certified	Many models are certified	Yes
PFAS	Varies a lot by model; check the certificate	Many models are certified	Yes, reduces the widest range
Nitrate	No	No	Yes
Trade-offs	Slow, small, cartridges need changing on time	Needs install under the sink	Costs the most, sends some water down the drain, strips minerals

About those minerals: Reverse osmosis (RO) does remove calcium and magnesium along with everything else. If you eat a varied diet, food supplies most of those minerals, and many RO systems add minerals back. Still, if you use one of these systems to remove the PFAS, don’t forget to focus on magnesium at dinner.

The mistake I see most often is buying the fanciest system for a problem you don’t have. If your report is clean and your house is newer, a certified pitcher or carbon block is probably plenty.

What I’d skip

A few water products cost real money without answering the question that matters for your hormones.

Bottled water as the fix

Several major bottled brands are purified municipal water, and you’re trading your tap for water that sat in plastic. I explained why that trade isn’t a hormone upgrade in my post on endocrine disruptors in plastics. A certified filter on your own tap is cheaper and lower-exposure.

TDS meters

A TDS (total dissolved solids) pen measures minerals in general. It can’t detect lead, PFAS or nitrate, so a “good” reading tells you nothing about the contaminants you care about.

Alkaline or hydrogen water

Alkaline and hydrogen water don’t remove anything, and there’s no good evidence they change your hormones. If the budget is limited, spend it on a lab test or a certified filter first.

Frequently asked questions

Find out what’s in your water

Can tap water make you sick? Rarely in the “I’ve got to run to the bathroom” way.

But the slower way deserves ten minutes of your attention, especially in the years when your estrogen, thyroid, and bones are all critical things to protect.

My free What’s In Your Water prompt reads your town’s report for you, compares the numbers to the current limits and tells you in plain language whether a filter is worth it and which kind.

Grab it, find your report, and find your real level of risk, fast.

This article is for informational and educational purposes only and is not medical advice. Please talk with your own clinician about your specific symptoms.

References

1. Centers for Disease Control and Prevention. About Drinking Water; Chemicals That Can Contaminate Tap Water. https://www.cdc.gov/drinking-water/about/index.html · https://www.cdc.gov/drinking-water/causes/chemicals-that-can-contaminate-tap-water.html
2. Ding N, Harlow SD, Randolph JF Jr, Calafat AM, Mukherjee B, Batterman S, Gold EB, Park SK. Associations of Perfluoroalkyl Substances With Incident Natural Menopause: The Study of Women’s Health Across the Nation. Journal of Clinical Endocrinology & Metabolism. 2020;105(9):e3169–e3182. Lay summary: https://news.umich.edu/pfas-exposure-may-lead-to-early-menopause-in-women/
3. U.S. Environmental Protection Agency. Per- and Polyfluoroalkyl Substances (PFAS) National Primary Drinking Water Regulation. https://www.epa.gov/sdwa/and-polyfluoroalkyl-substances-pfas · https://www.federalregister.gov/documents/2026/05/20/2026-10086/extending-the-compliance-deadline-for-the-pfoa-and-pfos-maximum-contaminant-levels
4. Ward MH, Kilfoy BA, Weyer PJ, Anderson KE, Folsom AR, Cerhan JR. Nitrate intake and the risk of thyroid cancer and thyroid disease. Epidemiology. 2010;21(3):389–395. https://journals.lww.com/epidem/abstract/2010/05000/nitrate_intake_and_the_risk_of_thyroid_cancer_and.18.aspx
5. Melzer D, Rice N, Depledge MH, Henley WE, Galloway TS. Association between serum perfluorooctanoic acid (PFOA) and thyroid disease in the U.S. National Health and Nutrition Examination Survey. Environmental Health Perspectives. 2010;118(5):686–692. https://pubmed.ncbi.nlm.nih.gov/20089479/
6. Agency for Toxic Substances and Disease Registry. Lead Toxicity: What Is the Biological Fate of Lead in the Body? https://archive.cdc.gov/www_atsdr_cdc_gov/csem/leadtoxicity/biologic_fate.html
7. Nash D, Magder LS, Sherwin R, Rubin RJ, Silbergeld EK. Bone density-related predictors of blood lead level among peri- and postmenopausal women in the United States: NHANES III, 1988–1994. American Journal of Epidemiology. 2004;160(9):901–911. https://academic.oup.com/aje/article-abstract/160/9/901/86517
8. U.S. Environmental Protection Agency. Basic Information about Lead in Drinking Water; Lead and Copper Rule Improvements. https://www.epa.gov/ground-water-and-drinking-water/basic-information-about-lead-drinking-water · https://www.epa.gov/ground-water-and-drinking-water/lead-and-copper-rule-improvements
9. U.S. Environmental Protection Agency. Consumer Confidence Reports (CCR). https://www.epa.gov/ccr
10. U.S. Geological Survey. Contamination in U.S. Private Wells. https://www.usgs.gov/water-science-school/science/contamination-us-private-wells
11. U.S. Environmental Protection Agency. Reducing PFAS in Your Drinking Water with a Home Filter. https://www.epa.gov/cleanups/reducing-pfas-your-drinking-water-home-filter
12. Gore AC, Chappell VA, Fenton SE, et al. EDC-2: The Endocrine Society’s Second Scientific Statement on Endocrine-Disrupting Chemicals. Endocrine Reviews. 2015;36(6):E1–E150. https://pubmed.ncbi.nlm.nih.gov/26544531/
13. Water & Wastes Digest. AP Finds Prescription Drugs in Drinking Water (summary of the Associated Press investigation, March 2008). https://www.wwdmag.com/home/news/10912955/ap-finds-prescription-drugs-in-drinking-water
14. Benotti MJ, Trenholm RA, Vanderford BJ, Holady JC, Stanford BD, Snyder SA. Pharmaceuticals and endocrine disrupting compounds in U.S. drinking water. Environmental Science & Technology. 2009;43(3):597–603. https://pubs.acs.org/doi/10.1021/es801845a
15. World Health Organization. Pharmaceuticals in drinking-water. 2012. https://www.who.int/publications/i/item/978924150208