Ferritin Levels: What They Mean for Your Iron, Energy, and Health

When your doctor checks your ferritin levels, a protein that stores iron in your cells and releases it when needed. Also known as serum ferritin, it's the best single indicator of how much iron your body has tucked away for future use. This isn’t about the iron in your blood—that’s serum iron. Ferritin is your body’s savings account for iron. If it’s low, you’re running on empty, even if your hemoglobin looks okay.

Low ferritin levels, typically under 30 ng/mL, are the earliest sign of iron deficiency. This happens before anemia shows up on a full blood count. People with chronic fatigue, hair loss, or restless legs often have low ferritin—even if they’re not anemic yet. Women with heavy periods, vegans, and people with gut issues like celiac or IBD are most at risk. On the flip side, high ferritin levels, over 300 ng/mL in men or 200 ng/mL in women, don’t mean too much iron intake—they usually mean inflammation, liver disease, or genetic conditions like hemochromatosis. Your body makes more ferritin when it’s fighting infection or dealing with chronic illness, so a high reading isn’t always about excess iron.

Many doctors only check ferritin if someone looks pale or tired, but it’s worth asking for—even if you feel fine. It’s a simple blood test, and fixing low ferritin early can stop fatigue, brain fog, and even heart strain down the road. Iron supplements work, but only if you take them right: on an empty stomach with vitamin C, and away from coffee, calcium, or antacids. And if your ferritin is high, don’t just take iron pills—you need to find out why it’s up.

What you’ll find in the posts below isn’t a textbook on iron. It’s real-world advice from people who’ve been there: how ferritin connects to thyroid function, why some people still feel tired even after taking iron, how menstrual blood loss quietly drains stores over years, and what tests to ask for when your doctor says "you’re fine" but you know you’re not. This isn’t about numbers on a lab sheet. It’s about understanding what your body is telling you—and how to listen.