Supplement Guide | Biomarkers 04 | Biomarkers Every Woman Should Know (Plus What They May Reveal)
Typical lab tests for annual physicals tend to focus on conventional standards. But they can miss some of the conditions women are more likely to face.
Women are more likely than men to develop autoimmune disease, thyroid disorders, iron deficiency, osteoporosis, and certain forms of cardiovascular disease. Many of these risks are shaped by female-specific biology, including menstruation, pregnancy, and menopause
Many of the biomarkers closely associated with these risks, including ferritin, TPO antibodies, fasting insulin, ApoB, and lipoprotein(a), are not routinely included in standard lab tests.
The biomarkers below are tools that can help identify some of the most common biological shifts women experience across the lifespan, sometimes even before those shifts become noticeable.
1. Ferritin
The hidden iron deficiency marker
Why it matters for women: Women lose iron through menstruation, pregnancy, childbirth, and breastfeeding. Iron depletion can develop before anemia appears on a standard panel.
What it may help uncover
Iron deficiency without anemia
Heavy menstrual bleeding
Postpartum depletion
Related symptoms may include
Fatigue
Hair loss
Headache
Shortness of breath
Generalized weakness
Why women are at higher risk: Iron deficiency is one of the most common nutritional deficiencies worldwide and disproportionately affects women of reproductive age. A 2025 systematic review of over 288,000 menstruating individuals found a pooled prevalence of iron deficiency around 27%, rising to 31% when adjusted for inflammation. U.S. data suggest the prevalence of iron deficiency without anemia in women may be as high as 40%.
Why ferritin specifically? Standard blood counts can miss iron deficiency. In one study of young women with heavy menstrual bleeding that used ferritin to identify patients with iron deficiency, fewer than half of iron-deficient cases were detected by hemoglobin or CBC alone.
2. TSH
The thyroid health marker
Why it matters for women Women are five to eight times more likely than men to develop thyroid issues, according to the American Thyroid Association (ATA). One in eight women will develop a thyroid disorder in her lifetime.
What it may help uncover
Hypothyroidism
Hyperthyroidism
Early thyroid dysfunction
Related symptoms may include
Fatigue
Weight changes
Depressed mood or anxious feelings
Temperature sensitivity
Fertility challenges
Why women are at higher risk: Thyroid disorders often emerge during periods of hormonal transition, including pregnancy, postpartum, and perimenopause. The ATA estimates that up to 60% of people with thyroid disease are unaware of their condition.
3. TPO Antibodies
The autoimmune thyroid marker
Why it matters for women Many women develop thyroid autoimmunity years before thyroid hormones become abnormal. TPO antibodies are present in over 90% of people with Hashimoto's thyroiditis.
What it may help uncover
Hashimoto's thyroiditis
Autoimmune thyroid disease
Future thyroid dysfunction risk
Related symptoms may include
Persistent fatigue
Brain fog
Cold intolerance
Sluggishness
Why women are at higher risk Hashimoto's is 7 to 10 times more common in women than in men. It is one of the causes of hypothyroidism in adults and, when left untreated, can increase your risk of high cholesterol, heart disease, and high blood pressure.
Antibody positivity can precede changes in TSH by years, which means monitoring this marker can give you early insight into thyroid autoimmunity risk before standard markers shift.
4. Vitamin D
The bone and immune health marker
Why it matters for women: Vitamin D supports bone strength, muscle function, and immune regulation. Deficiency is common in postmenopausal women even in sun-rich regions.
What it may help uncover
Increased osteoporosis risk
Poor bone health
Low vitamin D status
Related symptoms may include
Fatigue
Muscle weakness
Frequent illness
Why women are at higher risk: Vitamin D helps the body absorb calcium and maintain normal bone remodeling, both of which are essential for preserving bone strength.
As estrogen declines around menopause and bone loss accelerates, adequate vitamin D becomes increasingly important for skeletal health. A large real-world study of over 8,500 postmenopausal women found that more than 80% had vitamin D deficiency or insufficiency.
5. HbA1c
The long-term blood sugar marker
Why it matters for women: Changes in blood sugar regulation matter for fertility, pregnancy outcomes, cardiovascular disease, and healthy aging. HbA1c provides a window into how the body has been managing glucose over the previous two to three months and can help identify early metabolic shifts before symptoms appear.
What it may help uncover
Prediabetes
Type 2 diabetes
Elevated cardiovascular risk
Related symptoms may include
Often none, until disease is advanced.
Why women are at higher risk: Conditions such as PMOS (formerly PCOS), gestational diabetes, and menopause-related metabolic changes are associated with significantly increased future diabetes risk.
More than 50% of women with PMOS are estimated to develop type 2 diabetes before age 40. Women with a history of gestational diabetes also face substantially elevated lifetime risk. HbA1c is useful because it can characterize these trajectories even before glucose becomes overtly abnormal.
6. Fasting Insulin
The early metabolic health marker
Why it matters for women Insulin resistance frequently develops before glucose or HbA1c become abnormal. Fasting insulin can signal early metabolic dysfunction when other markers still look normal.
What it may help uncover
Early insulin resistance
PMOS-related metabolic dysfunction
Future diabetes risk
Peri/post menopausal metabolic changes
Related symptoms may include
Weight gain
Headaches
Sugar cravings
Fatigue after meals
Difficulty losing weight
Why women are at higher risk: Insulin resistance is a core feature of many cases of PMOS, occurring in up to 50% of women with the condition, including those who are not overweight.
It is also associated with gestational diabetes and the hormonal changes of perimenopause and menopause. Elevated fasting insulin has been linked to increased cardiovascular and metabolic risk and can appear before blood sugar levels become abnormal, making it a useful early marker of metabolic dysfunction.
7. ApoB
The cardiovascular risk marker
Why it matters for women: Women are often underdiagnosed and undertreated for cardiovascular disease despite it being their leading cause of death.
What it may help uncover
Hidden cardiovascular risk
Atherosclerosis risk
Elevated risk despite “normal” cholesterol
Why it may be more useful than LDL ApoB measures the number of potentially artery-clogging particles. For any given LDL cholesterol level, someone with smaller particles will usually have a greater number of them. A single LDL number can miss patients with many small, dense particles that carry higher atherogenic risk.
Why women should pay attention Cardiovascular risk often rises sharply after menopause as estrogen's protective effects decline.
Research from the Journal of the American Heart Association found that ApoB followed a U-shaped trajectory around the final menstrual period, declining in the years before menopause and then rising, in 84% of women tracked longitudinally.
8. Lipoprotein(a) [Lp(a)]
The inherited heart disease and stroke risk marker
Why it matters for women Most people are never tested despite Lp(a) being largely genetic and one of the strongest inherited cardiovascular risk factors. Elevated levels are present in 10 to 20% of the population.
What it may help uncover
Premature heart disease risk
Stroke risk
Aortic valve disease risk
Why women should pay attention Lp(a) concentrations are genetically determined in 70 to 90% of cases, meaning diet and exercise have minimal influence on levels.
Levels also tend to be 5 to 10% higher in women than men, and can increase further after menopause. Women with a family history of premature heart disease may carry elevated risk that standard cholesterol tests miss entirely.
9. hs-CRP
The inflammation marker
Why it matters for women High-sensitivity C-reactive protein (hs-CRP) can reveal even small amounts of inflammation in the body. Inflammation is involved in many conditions that disproportionately affect women.
What it may help uncover
Elevated cardiovascular risk
Inflammation related to autoimmune activity
Chronic metabolic dysfunction
Why women should pay attention: Studies have found CRP levels consistently higher in women than in men, even after accounting for hormone replacement therapy and other cardiovascular risk factors.
In a 2024 study that followed women for 30 years, elevated hs-CRP was independently associated with a higher risk of cardiovascular events, alongside LDL cholesterol and lipoprotein(a).
Women also bear a disproportionate burden of autoimmune and inflammatory conditions, making inflammation an important part of the broader cardiometabolic picture.
10. Estradiol
The multi-faceted hormone marker
Why it matters for women Estradiol influences reproductive health, fertility, bone density, cardiovascular function, and menopause symptoms. Circulating levels decrease substantially following menopause, and with them go a range of protective effects on physiology and metabolism.
What it may help uncover
Ovarian dysfunction
Menopause transition
Certain fertility issues
Related symptoms may include
Irregular periods
Hot flashes
Sleep disruption
Mood changes
Vaginal dryness
Why women should pay attention: Estradiol is the primary driver of bone mineral density in women. As it declines during perimenopause and menopause, bone resorption accelerates.
Research has shown that the rate of ovulatory cycle decline in perimenopause significantly correlates with the rate of bone mineral density loss, with 24% of women classified as fast bone losers in one two-year longitudinal study of 49 women. Estradiol also plays a direct role in cardiovascular and metabolic function, with postmenopausal estradiol decline linked to rising LDL, rising ApoB, and reduced HDL protective effect. Few biomarkers capture the major biological transitions of a woman's life as directly as estradiol.
What These 10 Biomarkers Reveal
Most women do not experience health changes one biomarker at a time. They experience transitions.
Iron stores change with menstruation and pregnancy. Thyroid autoimmunity can develop years before thyroid function changes. Insulin resistance often emerges before diabetes. Cardiovascular risk shifts after menopause. Bone loss accelerates as estrogen declines.
The value of these biomarkers is not in collecting more numbers. It is in recognizing these patterns earlier and understanding how they work as a system.
Taken together, these markers map the areas where women face some of the most common health risks:
Autoimmune disease: TPO antibodies, hs-CRP
Thyroid disease: TSH, TPO antibodies
Iron deficiency: Ferritin
Metabolic dysfunction and diabetes: Fasting insulin, HbA1c
Cardiovascular disease: ApoB, Lipoprotein(a), hs-CRP
Perimenopause and menopause: Estradiol
Bone health and osteoporosis: Vitamin D, Estradiol
No blood test can predict the future, but the right biomarkers can provide a clearer picture of the biological changes that shape women's health across a lifetime and help guide more informed conversations with a healthcare provider.