Can Low Iron Cause Weight Gain?

Iron is an essential trace mineral in foods like lean meats, poultry, nuts, seeds, and seafood. It is necessary for growth, cell functions, hormone production, and neurological (nervous system) development. Iron is also essential for creating hemoglobin, a protein in red blood cells that transports oxygen from the lungs to tissues.

Diet and health conditions can cause iron deficiency (low iron levels) and symptoms like fatigue, weakness, gastrointestinal (GI) pain, and decreased concentration and memory. In the United States, iron deficiency is common in populations such as pregnant people and young children. It can lead to iron-deficiency anemia, where the body does not have enough red blood cells.

Studies show an association between iron deficiency and obesity, a condition in which the body has excess fat cells. Obesity can increase your risk of health conditions, such as type 2 diabetes and heart disease.

Obesity may disrupt iron homeostasis, the body’s process of maintaining a balance of iron for essential bodily functions. This disruption can lead to iron-deficiency anemia.

Research suggests an association between obesity and low iron levels. Obesity triggers chronic (long-lasting) inflammation, increasing hepcidin levels. Hepcidin is a peptide hormone that reduces the intestines’ ability to absorb iron into the bloodstream, where it’s distributed throughout the body.

When overweight or obese individuals lost significant weight in these studies, they saw reduced chronic inflammation and hepcidin levels. This reduction led to increased iron absorption, which suggests weight loss may support iron absorption in the body. More research is needed to confirm this effect.

You can increase your iron intake by eating more iron-rich foods and supplementing with iron.

Incorporating more iron-rich foods into your diet can support your metabolism and reduce weakness and fatigue, especially if you are iron deficient. In addition to supporting metabolic processes, iron’s positive effect on energy levels makes it easier to exercise and be physically active, which can promote weight loss.

Some individuals may need to take iron supplements. While iron supplements are not a weight-loss tool on their own, they can increase your iron levels, which can support metabolism and energy levels. Always speak to a healthcare provider before adding new supplements to your routine.

Iron is also important for organ function and muscle health.

People with low iron may not have noticeable symptoms at first. Over time, low iron can progress to iron deficiency anemia, which can cause symptoms like:

• Digestive issues
• Weakness and/or fatigue
• Shortness of breath
• Difficulty concentrating
• Memory problems
• Cold hands and feet
• Decreased immune health (which can increase the risk of infections and other illnesses

In children, iron-deficiency anemia may contribute to learning difficulties.

Groups at higher risk of iron deficiency include people who are pregnant or breastfeeding, young children and infants, people with heavy periods, frequent blood donors, and people with certain health conditions such as cancer and heart disease. Some people with digestive conditions such as celiac disease or ulcerative colitis (UC) may also have trouble absorbing iron.

Common causes of iron deficiency include low consumption of iron from food, a digestive health condition that makes it harder to absorb iron, and blood loss. Here are some ways to improve your iron levels:

• Take a supplement: Iron supplements include ferrous sulfate, ferrous gluconate, ferric citrate, and ferric sulfate. Speak to your healthcare provider about the best dosage and form for you. Upper limits for iron are 40 milligrams (mg) for babies and children up to age 13 and 45 milligrams for people over age 14. Doses above the upper limit may cause side effects such as nausea, abdominal pain, and constipation.
• Eat more fortified foods: Eat more iron-fortified foods such as fortified whole-grain breads and cereals.
• Eat more iron-rich foods: Non-heme iron is found in plant-based foods such as beans, nuts, and seeds. Foods such as meats, poultry, and seafood contain both heme and non-heme iron.
• Consume iron with vitamin C-rich foods: Pairing vitamin C with iron increases the body’s absorption of iron, especially non-heme iron from plant sources. Foods rich in vitamin C include citrus fruits, tomatoes, and peppers.

Eating a nutritious, balanced diet and staying physically active are important for weight management. Other strategies to manage and maintain your weight include:

• Get enough sleep
• Manage your stress levels—for example, by incorporating more relaxing activities into your daily routine, such as deep breathing, meditation, yoga, or spending time outdoors
• Limit foods and drinks high in added sugars, like soda, candy, and baked goods

Consult a healthcare provider for a personalized plan that supports your lifestyle and weight-loss goals. While weight gain is not a side effect of low iron, studies show that it is more difficult to lose weight if you have low iron levels.

Iron is a trace mineral that supports growth, development, red blood cells, and hormone synthesis.

While anemia is not a direct cause of weight gain, being overweight or obese can disrupt iron homeostasis and lead to anemia. Research also shows that iron deficiency may affect weight loss by leading to metabolic changes that make it harder to lose weight.

If you suspect you are low or deficient in iron, see a healthcare provider for diagnosis and treatment. Treatment options may include taking iron supplements and eating more iron-rich foods to increase your levels.