You may not know this, but one of the best indicators of a person’s overall health, is the condition and appearance of the fingernails. Nails are always growing, and because of this, they reflect many of the nutrient levels and nutrition quality of the person as a whole. If the diet is missing any key vitamins or nutrients, the evidence of it is often on display within or around the fingernails.
A change in the colour, shape, texture or feel of your nails can indicate a deficiency. Keeping an eye on them can help you to identify a problem, or help assure you that there isn’t one.
Biotin, or vitamin B7 (also known as coenzyme R and as vitamin H), promotes healthy cell growth and plays a part in metabolism of amino acids that help build proteins. It is essential for nail growth. If your system is low on vitamin B7, your fingernails will start to become brittle, and can break more easily than they normally would when healthy.
Deficiencies in biotin are rare, however, possibly because it is found in foods common to both wide-ranging diets and stricter ones. Biotin can be found in organ meats, like liver and kidneys, and in dairy products and eggs (in the yolk, so egg-white omelettes aren’t a good source). Vegetables like cauliflower and sweet potatoes contain biotin, as do avocados. Salmon is rich in biotin, as are nuts and seeds, and it is also found in yeast – and therefore in many products made with yeast, such as breads and some baked goods. Learn more about foods with biotin in here.
Summary Biotin may help strengthen brittle nails or prevent brittleness in nails. Biotin deficiency is rare, as it is found in sufficient amounts in many common foods.
2. Other B Vitamins
As well as biotin, other vitamins from the B complex are important for nail health and growth. B12, for example, plays a part in the absorption of iron, and in the development of red blood cells which carry oxygen throughout the body, including extremities such as fingernails and toenails. B12, as well as the iron it helps out bodies to absorb, are both vital in keeping nails healthy and strong.
A deficiency of vitamin B12 can sometimes be detected by examining the nails. If nails appear blue in colour, or have wavy steaks or brown discolouration on or within them, then you should seek a doctor’s advice. In the meantime, increasing your intake of B12 won’t hurt.
You can find natural sources of B12 in meat, poultry, fish, eggs and dairy products. Don’t worry if you’re a vegetarian or vegan though, as many food products are fortified with B12.
A similar vitamin, called B9 or folate, is also important to nail growth and health as if assists in red blood cell formation and the development of new cells. If nails appear rigid and/or brittle, or are discoloured, you may have a deficiency of B12. This can occur more often in pregnant women, as their bodies have a greater demand for cell-forming components and processes.
You can get folate from eating dark green vegetables, citrus, lentils, peas, seeds and nuts, and even avocado.
Summary Both vitamin B12 and folate are important to red blood cell production and oxygen transportation to your fingernails and toenails. A deficiency can cause nail weakness or discolouration of your nails.
Iron is important to every cell in the human body, and your nails are no exception. Iron is a main component of red blood cells, and without it, oxygen can’t be transported to the other cells in your body, causing the gradual failure of many systems. Parts of your body that are further from the lungs will show damage earlier, and since the nails are at the end of the fingers and toes, they reflect iron deficiency quite soon.
Signs include vertical ridges in your nails, and they may start to curl into a concave shape, curling upward like spoons rather than downward over the ends of your fingers.
Women tend to need more iron than men do, so it is even more important for them to ensure that they are takin gin enough iron, even when they are not pregnant.
Good sources of iron include most food derived from animals. This includes meat, like beef, chicken, and fish, but also eggs and some dairy products. Iron is also found in seeds, in dark green leafy vegetables and in legumes like peanuts and beans. If you derive your iron exclusively or mainly from vegetable products, it is important to take in enough vitamin C too, as it helps your body to absorb iron. Of course, most vegetarian diets are rich in vitamin C anyway, so this is usually not a problem. To be safe though, many vegetarians take a supplement or eat fortified foods.
Many foods that wouldn’t otherwise have iron are fortified with it, so keep an eye on labels even when you might not think the food would be a good source of iron. Examples of this are breakfast cereals and some breads and baked products.
Summary Iron plays a big role in supplying your body with oxygen, so make sure you have enough. Vitamin C helps with absorption of iron, so they work well together.
Magnesium isn’t a vitamin; it’s a mineral. You might not think minerals are all that important to your health, but they are vital to life and the proper running of many of your body’s processes – over three hundred of them in fact!
Magnesium assists in protein synthesis and cell growth. A deficiency often shows up as vertical ridges in the nails – similar to the signs of iron deficiency in fact. Unlike iron, however, fewer than sixty percent of Americans get the amount of magnesium they need. Men need more magnesium than women do, mainly due to average size differences, but it is very important to both sexes.
Good sources of magnesium include whole grains, like wheat or quinoa; dark, leafy vegetables, like spinach; nuts, like almonds, peanuts and cashews; black beans, and edamame.
Summary Magnesium helps with protein synthesis and the formation of new nails. Most Americans don’t get the recommended amount, and so it is important to keep an eye on this one.
Nails are mostly made up of a protein called keratin; it’s the same protein that makes up your hair. It’s strong, flexible, and tends to be shiny. It not only makes up the basic structure of your nails, it also protects them from damage caused by injury or repeated actions.
We talk about ‘healthy nails,’ but in reality the cells you see on your fingernails are already dead (same with your hair). New cells push up from your nail beds (underneath your nails) as the body sheds the dead cells at the surface. This is the normal process, and isn’t anything to worry about. However, weak live cells underneath lead to weak dead cells on the surface, so it is important that we eat enough protein to feed the cells and keep the whole system healthy and fuelled up.
The richest sources of protein are animal foods, like meat, fish, eggs and dairy products, but other adequate sources include many vegetables, including lentils, seeds, nuts, whole grains, legumes, and soy.
Summary Adequate protein intake keratin, which is necessary for strong, healthy nails.
6. Omega-3 Fatty Acids
‘Omega-3 fatty acids’ sounds really complex and scientific, but just think of them as lubricants and moisturisers for your nails. Omega-3s are part of what gives nails that shiny, smooth look, but they probably do more than that. They may also reduce inflammation within the ail bed itself, which helps keep the growth process in good health. Without them, nails become dry, brittle, and dull-looking.
The best sources for omega-3s include salmon, trout, mackerel, tuna and sardines, but you can also get them from chia seeds, eggs, walnuts and soy.
Summary Omega-3 fatty acids lubricate and moisturise nails and help to give them a shiny, healthy appearance.
7. Vitamin C
Vitamin C helps produce collagen, which is a protein that gives rigidity, shape and strength to hair and nails – among other beneficial functions.
Vitamin C deficiency usually results in slow nail growth, or brittle nail structure. Unlike vitamin D, vitamin C cannot be produced by the body, so 100% of our vitamin C needs have to come through our diets. Citrus fruits, strawberries, kiwi fruit, tomatoes, green vegetables, and bell peppers are all good sources of vitamin C, and it is also included in almost every multivitamin supplement.
Summary Vitamin C promotes string nails by helping in the production of collagen.
Zinc is another mineral that is crucial to health, especially with regard to healthy skin and nails.
Since it assists in the development and division of cells, and nail cells grow and divide relatively quickly, a deficiency in zinc can cause immediate problems. If you don’t get enough of it, the nail plate will degenerate. A sign of this happening is the appearance of little white spots in the nails.
Excellent sources of zinc include meat and dairy products like beef, chicken, fish, eggs and cheese, but you can also get it from vegetable sources like black beans, chickpeas, nuts, soy and many types of seeds.
Summary Zinc helps cells grow and divide, so it is essential for your fast-growing nails. White spots in the nail is a sign of deficiency.
Supplements vs Food Sources
The best way to get the vitamins and minerals you need is always through natural food sources (or in the case of vitamin D, the sun). Our bodies are excellent at pulling what we need from the right kinds of healthy foods.
Many modern diets, however, are not as varied or balanced as they should be, and so many people turn to supplements to make sure they are receiving the vitamins and minerals they need. This is a good idea, but a word of caution is needed.
We know what these vitamins and minerals do for our nails, but scientific evidence that taking supplements is an effective way of getting these valuable substances into our bodies is lacking in many cases. In fact, the only one for which there is a link between a supplement and nail health, is biotin. That isn’t to say that the others don’t work, but the effect has not been adequately demonstrated in many cases.
For this reason, it is recommended that your primary goal is to get these resources directly from your diet – but if you are not sure you are getting enough of each of them, then supplements may be of some help.
Summary A healthy and varied diet is the best way to get all of the vitamins and nutrients you need, but if you’re not getting enough, or aren’t sure you are, taking a supplement may be a beneficial backup.
If you prefer to take supplements to keep things simple, then see our hair skin and nails vitamin gummies here.
The Bottom Line
There is scientific evidence that a healthy diet, including foods rich in the vitamins and minerals listed here, will contribute to the growth and sustainability of healthy nails. There is little scientific evidence, however, that supplements have the same effect.
The best plan then, is to eat a healthy diet – including plenty of fruit, vegetables, and nuts, as well as protein-rich foods and foods rich in omega-3 fatty acids.