What minerals are
Minerals are inorganic elements that the body needs in small to moderate amounts to work normally. Unlike some vitamins, the body cannot make them, so they have to come from food and drink. They are often split into two groups: major minerals, needed in larger amounts, such as calcium, magnesium, potassium, sodium and phosphorus; and trace minerals, needed in tiny amounts, such as iron, zinc, iodine, selenium and copper.
This article is general information, not medical advice. How much of each mineral a person needs depends on age, sex, pregnancy, health conditions and medications, so check with a doctor or registered dietitian if you have concerns, and before using any supplement. The aim here is to describe common roles and food sources, not to suggest amounts.
Magnesium
Magnesium is involved in many processes in the body, including muscle and nerve function and the way cells make energy. It is also a component of bones.
Foods that typically contain magnesium include:
- Leafy green vegetables such as spinach
- Nuts and seeds, including almonds, cashews and pumpkin seeds
- Legumes such as black beans and chickpeas
- Whole grains, including oats, brown rice and whole wheat
- Some fish and dairy products
Refining grains tends to remove part of their magnesium, which is one reason whole grains are often recommended. Because kidneys regulate magnesium, people with kidney problems should be especially careful and take advice before changing intake.
Iron
Iron helps carry oxygen in the blood as part of hemoglobin and is also involved in other cell functions. Too little iron over time can lead to a type of anemia, but tiredness has many possible causes, so it is worth getting symptoms checked rather than guessing.
There are two forms in food. Heme iron comes from animal foods such as red meat, poultry and fish, and is generally absorbed more readily. Non-heme iron comes from plants and fortified foods, including lentils, beans, tofu, spinach, fortified cereals and some seeds. Eating a vitamin C-rich food such as citrus or peppers in the same meal is commonly said to improve non-heme absorption, while tea, coffee and some high-calcium foods can reduce it when taken with the meal. Our article on vitamin C looks at that nutrient separately.
Iron is one mineral where more is not better. Too much can be harmful, and some people store excess iron because of a medical condition, so iron supplements should only be used on professional advice.
Calcium
Calcium is best known for bones and teeth, and it also plays a part in muscle contraction and nerve signaling. Dairy foods such as milk, yogurt and cheese are common sources. Others include fortified plant milks and tofu made with calcium, canned fish eaten with the soft bones, and some leafy greens such as kale and bok choy. Vitamin D influences how well the body uses calcium, which is one reason the two are often discussed together; our piece on vitamin D covers that side.
Zinc
Zinc is involved in growth, wound healing and the normal functioning of the body’s defense systems. Typical sources are shellfish, meat, poultry, beans, nuts, seeds and whole grains. Plant sources contain compounds that can reduce absorption somewhat, so people who eat little or no animal food sometimes need to pay closer attention to variety. Soaking, sprouting and fermenting are sometimes mentioned as ways to improve absorption from plant foods.
Potassium
Potassium helps with fluid balance, nerve signals and muscle function, and it works alongside sodium. Many fruits and vegetables supply it, including bananas, potatoes, beans, avocados, tomatoes and leafy greens, as well as yogurt and some fish. People with kidney disease or those taking certain blood pressure medications may need to limit potassium, so personal advice matters here. Sodium is the mineral most people hear about in the opposite direction, and sodium intake is covered separately.
Other minerals worth knowing
- Iodine supports the thyroid. Sources include seafood, dairy and iodized salt.
- Selenium is found in nuts (Brazil nuts are notably rich), seafood, eggs and grains. Very high intake can be harmful.
- Phosphorus works with calcium in bones and is widespread in protein foods, dairy and grains.
- Copper is present in shellfish, nuts, seeds and whole grains.
A food-first approach
For most healthy people, eating a varied diet that includes vegetables, fruit, whole grains, legumes, nuts, seeds and a mix of protein foods covers the common minerals reasonably well. A broader look at how those groups fit together is in the guide to a balanced diet. Some groups have a higher chance of falling short on particular minerals, for example people who menstruate heavily, pregnant people, those on very restrictive diets, and some older adults. Others may absorb less because of digestive conditions or medications.
Minerals also compete and interact. High doses of one can interfere with absorption of another, and some supplements interact with medicines. For that reason, a blood test and a conversation with a doctor are a better route than self-prescribing. The wider topic of dietary supplements, including how to read labels, has its own article.
Practical takeaways
- Look for variety across food groups rather than hunting for one “mineral-rich” food.
- Choose whole grains, beans, nuts and seeds regularly if they suit you.
- Pair plant-based iron sources with fruit or vegetables that contain vitamin C if you like.
- Treat persistent tiredness, cramps or other symptoms as a reason to see a professional, not as proof of a particular deficiency.
Individual needs vary, and a qualified professional can tell you whether your own intake needs attention.