Do We Have Metals in Our Body and Why Are They Essential?

Yes, your body contains metals, and about ten of them are essential, meaning you can’t live without them. They aren’t bits of solid metal. They exist as dissolved, electrically charged particles bound to proteins and fluids, where they carry oxygen, power nerves, build bone and run enzymes. The same chemistry that makes them useful also makes them risky, so the body keeps each one in a tight balance between too little and too much.

The Ten Metals Your Body Needs

Inside you, metals exist as ions: atoms that have lost electrons and so carry an electric charge. Ions dissolve in the fluids of your body and attach to proteins, which is why the body can move them around and put them to work.

Sodium, potassium, magnesium and calcium are needed in relatively large amounts.9PubMed. Essential metals in health and disease The other six are needed only in traces, yet they are just as essential.10PubMed. The essential metals for humans: a brief overview Calcium is the most abundant metal in the body mainly because bones are large, not because it outranks the others.

What Each Metal Does Inside You

A protein is a long folded chain, and on its own the chain often can’t grab oxygen or pass electrons along. A metal supplies a chemical handle at the protein’s working spot. Take the metal away and the protein loses its job.

Iron sits at the centre of heme, the part of hemoglobin that grabs oxygen.11PubMed Central. Mitochondria and Iron: Current Questions Heme also stores oxygen in muscle and helps cells make energy.12PubMed. The role of transporters in cellular heme and porphyrin homeostasis Heme-based proteins in the liver help break down medicines as well.13PubMed. The role of transporters in cellular heme and porphyrin homeostasis

Sodium and potassium power your nerves. Cells constantly pump sodium out and potassium in.14Encyclopædia Britannica. Nervous system That leaves the inside of a nerve cell slightly negatively charged, like a charged battery.15Encyclopædia Britannica. Nervous system A nerve signal starts when sodium suddenly rushes back in.16Encyclopædia Britannica. Nervous system The charge across the cell’s membrane flips briefly, and that flip is the signal itself. Potassium then flows out, which helps restore the resting charge so the nerve can fire again. The pumps move both metals back to where they started, a big ongoing energy cost for nerve cells.

Magnesium unlocks energy. ATP is the cell’s energy molecule,17PubMed Central. Mitochondrial Mg2+ homeostasis decides cellular energy metabolism and vulnerability to stress but it works mainly when bound to magnesium.18PubMed Central. Mitochondrial Mg2+ homeostasis decides cellular energy metabolism and vulnerability to stress

Calcium and phosphate form the mineral that makes bone hard.19PubMed. Calcium and phosphate: a duet of ions playing for bone health Bone isn’t a fixed structure, though. It is living tissue, constantly broken down and rebuilt, and it works as the body’s calcium reserve. A small amount of calcium circulates in blood and fluids, where it triggers muscle contraction and helps release signals between nerve cells. Because blood calcium matters so much, the body keeps it steady by drawing on bone when needed. A shortfall in the diet is therefore usually paid for from the skeleton, and blood levels may look normal at first.

Copper helps with the final step that turns oxygen into energy.20Linus Pauling Institute. Copper It is also needed to cross-link collagen and elastin into strong, flexible tissue,21Linus Pauling Institute. Copper and it helps prepare iron so blood can carry it to bone marrow.22Linus Pauling Institute. Copper Zinc holds the shape of a large family of proteins, which are coded for over 5,000 times in human genes.23PubMed Central. Structures and biological functions of zinc finger proteins and their roles in hepatocellular carcinoma Manganese runs an enzyme in mitochondria that neutralises harmful oxygen by-products.24PubMed Central. Manganese Superoxide Dismutase Dysfunction and the Pathogenesis of Kidney Disease Cobalt is the core of vitamin B12, which helps process some amino acids and fats.25PubMed Central. Relationship between Vitamin B12 and Cobalt Metabolism in Domestic Ruminant: An Update

What Happens When You Don’t Get Enough

Iron and zinc deficiencies are major health problems worldwide.26PubMed Central. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains Anemia and zinc deficiency each affect a large share of the world’s population, mostly in developing countries.27PubMed Central. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains Low iron and zinc are linked to anemia, stunted growth, weaker immunity, worse infections, pregnancy problems and slowed brain development in children.28ARS (Agricultural Research Service). Addressing Iron and Zinc Deficiency Across the Globe29ARS (Agricultural Research Service). Addressing Iron and Zinc Deficiency Across the Globe

Low iron brings tiredness, shortness of breath on exertion and pale skin. These come from blood carrying less oxygen. These symptoms have many causes, so a blood test checking hemoglobin and ferritin is needed to confirm low iron.

Iron deficiency develops slowly. The body first draws down its stored iron, so early deficiency may cause no symptoms at all. Only when stores run low does hemoglobin start to fall, which is when anemia appears. A person can feel run down and have low iron stores while blood counts still look normal.

The people most at risk are those who menstruate heavily or are pregnant, young children growing fast, and people eating mostly plant foods without planning. Ask a doctor before self-treating with supplements.

Other metals cause trouble too. Low magnesium or potassium can cause muscle cramps or heart rhythm problems. Low calcium over years weakens bones. Low B12, which depends on cobalt, causes anemia and nerve problems.

How Your Body Stores and Controls Metals

In blood, iron travels bound to a carrier protein called transferrin.30Journal of Pediatric Urology. Metals in Brain, Metal Transport, Storage and Homeostasis Extra iron is stored inside ferritin, a hollow protein shell holding up to 4,500 iron atoms.31Journal of Pediatric Urology. Metals in Brain, Metal Transport, Storage and Homeostasis That keeps iron in a safe, non-toxic form until it’s needed.32Journal of Pediatric Urology. Metals in Brain, Metal Transport, Storage and Homeostasis Other proteins grab zinc and copper, and also toxic metals like cadmium and mercury.33Journal of Pediatric Urology. Metals in Brain, Metal Transport, Storage and Homeostasis

A metal ion floating free in a cell can react with other molecules in unwanted ways, as the next section explains. Binding it to a protein keeps it from reacting, and the cell can release the metal only where and when a job needs it.

This is also what ferritin on a blood test reflects: how much iron you have stored. Low ferritin often signals low iron stores before anemia sets in. High ferritin can mean excess iron or inflammation, so a doctor needs to interpret it.

Some inherited conditions break these handling systems.34PubMed Central. Genetic Disorders Associated with Metal Metabolism Metals can then build up in organs, especially the brain.35PubMed Central. Genetic Disorders Associated with Metal Metabolism

When Metals Turn Harmful

When metal balance breaks down, free iron reacts with hydrogen peroxide to form highly reactive molecules that grab electrons from whatever is nearby, and they are the most destructive oxidisers in the body.36PubMed Central. The role of redox-active iron, copper, manganese, and redox-inactive zinc in toxicity, oxidative stress, and human diseases37PubMed Central. The role of redox-active iron, copper, manganese, and redox-inactive zinc in toxicity, oxidative stress, and human diseases They can damage DNA, proteins and fats in cell membranes.38PubMed. Redox- and non-redox-metal-induced formation of free radicals and their role in human disease Hydrogen peroxide is a normal by-product of cell chemistry, which is why loose iron is a risk.

Toxic metals cause harm differently. Lead and cadmium resemble calcium and zinc chemically,39PubMed Central. Heavy Metals and Human Health: Possible Exposure Pathways and the Competition for Protein Binding Sites so they can take the place of essential metals in proteins.40PubMed Central. Heavy Metals and Human Health: Possible Exposure Pathways and the Competition for Protein Binding Sites The protein then stops working properly.41PubMed Central. Heavy Metals and Metalloids As a Cause for Protein Misfolding and Aggregation People meet lead in old paint and old pipes, and tobacco smoke is a common source of cadmium. Testing water in older homes and quitting smoking reduce exposure.

More is not better with supplements. Iron pills beyond your need can overload storage. Accidental iron overdose is dangerous for children, so store pills out of their reach. Take metal supplements only for a known need.

Getting Metals From Food

A varied diet supplies all of these metals. Iron comes from red meat, beans, lentils and spinach. Zinc comes from shellfish, meat and seeds. Calcium comes from dairy, fortified plant milks and leafy greens. Potassium and magnesium come from fruit, vegetables, nuts and whole grains. Sodium comes from salt, mostly in processed foods.

Absorption matters as much as intake. Grains and legumes contain a compound that binds iron and zinc.42PubMed Central. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains Humans lack the enzyme to break it down,43PubMed Central. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains so less iron and zinc reach your blood from these foods. Soaking, sprouting or fermenting grains and beans lowers the amount of this compound. Tea and coffee with meals can reduce iron uptake, while pairing plant iron with vitamin C foods helps absorption.

Iron in meat is mostly heme iron, which the gut absorbs fairly easily. Iron in plants is non-heme iron, which is absorbed less well and is more affected by other foods in the meal. People who eat little or no meat may therefore need to plan their iron intake more carefully.

Metals Used in Medicine

Lithium salt is a standard treatment for bipolar disorder.44Periodic Bubbles. Elements in Medicine: Scans, Drugs and Implants Explained Platinum drugs such as cisplatin and carboplatin kill cancer cells by binding their DNA,45ES General. Role of Metal Ions in Biological Systems: Structure, Function and Therapeutic Implications and cisplatin transformed the outlook for testicular cancer.46Periodic Bubbles. Elements in Medicine: Scans, Drugs and Implants Explained Gadolinium contrast makes tissues stand out on MRI.47ES General. Role of Metal Ions in Biological Systems: Structure, Function and Therapeutic Implications Technetium-99m is used in nuclear medicine scans.48ES General. Role of Metal Ions in Biological Systems: Structure, Function and Therapeutic Implications Free gadolinium is toxic, so it is wrapped in a molecule until it leaves the body.49Periodic Bubbles. Elements in Medicine: Scans, Drugs and Implants Explained Because the kidneys clear it, anyone with kidney problems should tell the scanner team before a gadolinium scan.

Lithium has a narrow gap between a helpful dose and a harmful one, which is why people taking it have regular blood tests to check the level. Dehydration, some other medicines and kidney problems can raise the level, so they matter to mention to a prescriber. Severe tremor, vomiting or confusion should be taken seriously and reported promptly.

Why Life Depends on Metals

Iron was plentiful in early oceans and became life’s first key metal.50PubMed Central. Iron: Life’s primeval transition metal When oxygen built up, iron became scarce and copper and zinc became more available,51PubMed Central. Iron: Life’s primeval transition metal so cells evolved to use these other metals too.52PubMed Central. Iron: Life’s primeval transition metal