The goal of routine blood test is to learn how well your body is working and to diagnose diseases such as diabetes or heart disease that might not have obvious symptoms.
Four blood tests in particular are important to determine the state of your health according to the Harvard University.
1. Blood sugar test
- What it measures: The level of glucose (sugar) in your blood. Elevated blood sugar is a sign that your body either isn’t making enough insulin—the hormone that moves sugar into the cells to be used for energy—or isn’t using insulin efficiently. High blood sugar levels can indicate that you have diabetes or prediabetes.
- How often you need it tested: Your fasting glucose level or your HbA1C should be checked once a year, or more often if your blood pressure is high.
- What’s healthy: Less than 100 milligrams per deciliter (mg/dL) on a blood sugar test and an HbA1C of less than 5.7%.
- What to do if your levels are high: If you’re in the borderline, prediabetes range of 100 to 125 mg/dL, lifestyle changes can prevent you from progressing to full-blown diabetes. Eating a healthy diet, losing weight, plus getting at least 150 minutes of exercise per week can cut your risk of getting type 2 diabetes in half.
2. Lipid panel
- What it measures: Levels of unhealthy cholesterol and triglycerides to assess your heart disease risk.
- How often you need it tested: Women who are at increased risk for heart disease or who have diabetes should get tested once a year. Those who are at normal risk should ask their doctors about testing frequency.
- What’s healthy: total cholesterol of less than 200 mg/dL; HDL cholesterol of more than 50 mg/dL; LDL cholesterol of less than 130 mg/dL (less than 100 mg/dL for women at high risk for heart disease); and triglycerides of less than 150 mg/dL.
- What to do if your levels are high/low: Limit unhealthy fats from red meat, whole-fat dairy products, and fried foods. Also watch high-cholesterol foods such as egg yolks, cheese, and shellfish. Eat more of foods that lower unhealthy cholesterol—including nuts, fish, oatmeal, and vegetable oils.
3. Thyroid-stimulating hormone (TSH) and T4 test
- What it measures: The thyroid is a gland in the neck that produces hormones that regulate metabolism. Women are more likely than men to have an underactive thyroid gland (hypothyroidism) or overactive thyroid gland (hyperthyroidism). The TSH and T4 tests measure hormone levels to make sure your thyroid is working correctly.
- How often you need it tested: If you’re over 60, talk to your doctor about getting tested. Also get your levels checked if you have symptoms of hypothyroidism or hyperthyroidism, which include
- fast heartbeat
- increased appetite
- greater sensitivity to cold
- muscle weakness
- brittle hair and nails
- weight gain or loss.
- What’s healthy: TSH of 0.4 to 4.0 milli-international units per liter (mIU/L) and T4 of 4.5 to 11.2 micrograms per deciliter (mcg/dL).
- What to do if your levels are high/low: Hypothyroidism is treated with synthetic thyroid hormone taken daily by mouth. Hyperthyroidism is treated with radioactive iodine, antithyroid medicine, or surgery.
4. Vitamin D (25 hydroxyvitamin D) test
- What it measures: Levels of vitamin D in your blood. Vitamin D is essential for bone strength and other important functions in the body. Older women are more likely to have vitamin D deficiency, because our skin doesn’t produce this vitamin as efficiently from sun exposure as we age, and because we spend less time outdoors.
- How often you need it tested: The test needed is based on your age, diet, and level of sun exposure.
- What’s healthy: More than 30 nanograms/milliliters (ng/mL)
- What to do if your levels are low: Eat more foods containing vitamin D, such as dairy and fortified orange juice. If needed add a vitamin D supplement.