How often do you think about your fingernails and toenails? Do you think of your nails as a reflection of your overall health or are you just concerned with their cosmetic appearance? Although nice looking nails are a plus, no matter how you go about acquiring them, the way your nails appear naturally, without the help of a manicurist, can tell you a lot about your general health. What do normal nails look like without artificial nails, nail art, or nail polish?
What do healthy nails look like?
Let’s compare healthy nails versus unhealthy nails. Healthy nails have pinkish nailbeds and are smooth and uniform looking. They don’t have pits or ridges, aren’t discolored, and don’t break or flake easily. Some irregularities are somewhat normal; for example, a white spot on a nail can indicate an injury, while longitudinal ridges can be a normal sign of aging.
On the other hand, some nail irregularities can indicate a potential underlying health condition. But just because you have a certain nail appearance doesn’t mean you have an associated condition; it just means you should have your health-care professional take a look.
Some common nail irregularities and what they might mean:1
- Pitted nails that have tiny indentations are seen in individuals with psoriasis or autoimmune-related alopecia (hair loss). Psoriasis can also cause the nails to become very thick.
- Spoon-shaped nails are sometimes seen in individuals with hypothyroidism or liver disease.
- Anemia can result in spoon-shaped nails, and also nails that are very pale in color. Red blood cell counts, hemoglobin, and iron levels should be checked and corrected with supplementation if indicated.
- Horizontal ridges often indicate a sudden but temporary stoppage of nail growth, which could be caused by stress, high fever, or certain medications. They can sometimes also be caused by poor circulation.
- A nail separated from the nailbed can be caused by infection or injury.
- Although white spots on nails are often caused by trauma to the nail and will grow out, other potential causes include a zinc deficiency, allergies, or a fungal infection. Nail fungus can also cause nails to thicken and crumble.
- In addition to anemia, very pale nails can be seen in cases of congestive heart failure or liver disease.
- Blue nails are often a sign of poor oxygenation because of lung or heart disease. Blue or white nails can also be caused by Raynaud’s syndrome, which causes the small blood vessels feeding the fingers to spasm in response to cold or stress.2
- Dark lines or spots under nails, if not caused by trauma, could be a sign of melanoma and should be checked out.
- Brittle nails are the most common nail concern and have numerous causes, as discussed below.
Brittle nails: Causes and how to strengthen nails
Nail brittleness occurs in approximately 20 percent of the population and is most common in women over 50.3 Brittle nails have many causes and are one of the primary reasons a person might seek nutritional support for nail health. But what causes brittle nails? The most common causes of brittle nails are external exposures. Although it might seem counterintuitive, frequently having your hands in water can contribute to dry, brittle nails. Brittle nails can also be caused by use of nail polish, nail polish remover, and alcohol-based hand sanitizers.1
Dehydration is often cited as a cause of brittle nails, although this is controversial. Based on the oft-repeated statements that fingernails of well-hydrated individuals are 18-percent water, while dehydration results in fingernails that are 16-percent water or less, and that brittle nails have lower water content, researchers designed a study of 102 healthy individuals to test this hypothesis.4 What they found was that brittle nails had 12.48-percent water, while normal nails had 11.9-percent water. What they also found was that the odds of having brittle nails was 3.23-times greater in participants who had frequent manicures. Another study found water content of nails was significantly lower in winter than in summer.5
Low biotin is associated with brittle nails, while low levels of essential fatty acids (EFAs) – such as EPA, DHA, and GLA – are associated with nail desquamation, or flaky nails.6
There are several things to consider for brittle nails treatment. In terms of nutritional approaches, biotin is the best documented nutrient for brittle nails.* A review of published clinical trials found support for oral biotin to improve thickness and hardness of brittle nails.*7 Three studies found that 2.5 mg of biotin daily improved nail thickness, reduced nail splitting, and resulted in firmer, harder nails.8-10 Because low levels of EFAs are associated with brittle nails, adding a fish oil supplement or regularly consuming high-fat fish like salmon or trout might improve nail strength.*
There are other things to consider when approaching how to make nails stronger. Wear gloves when you are immersing your hands in water for an extended period of time. Avoid overuse of nail polish and use of acetone-based nail polish removers. Use moisturizing lotions you work into the nail beds and cuticles when applying to your hands. Stay hydrated – it certainly can’t hurt and just might help. Thorne’s Collagen Plus includes collagen peptides and a hydrating botanical from Japanese white peach to support healthy skin, hair, and nails.*
What about your cuticles?
A conversation about healthy nails would not be complete without a discussion about healthy cuticles versus unhealthy cuticles.
Cuticles are the areas of skin where it meets the nail. The cuticle has an important function – to protect the growth bed of the nail. They are not meant to be cut because it removes the protection of the growth bed and can lead to infection. If they start to grow over the fingernail, then they can be pushed back with a cuticle or orange stick – so called because they were originally made from the wood of orange trees.
Healthy cuticles are soft. If they are frequently cut, then they can become hard and more likely to split. You can maintain soft cuticles just like you would other areas of your skin – by using a good moisturizing lotion. You also can get hot wax treatments at a nail salon to soften the cuticles.
Frequent exposure to water, such as when washing dishes, can dry out cuticles just like it does nails. Wear gloves when possible. Nail polishes with acetone dry out the cuticles and should be avoided. And a last bit of advice: Avoid nibbling on your cuticles.
As you can see, nail care involves more than just how to get healthy nails. While having healthy nails can benefit your overall health by preventing infections, fungal overgrowth, etc., keeping an eye on your nails can also give you clues to potential underlying health issues.
※ This article is transplanted from Thorne's website and partially edited for Asian region. Original one is here.
- Can your nails show signs of an illness? https://www.scripps.org/news_items/6820-can-your-nails-show-signs-of-an-illness [Accessed 12.1.22]
- Raynaud’s disease. https://www.mayoclinic.org/diseases-conditions/raynauds-disease/symptoms-causes/syc-20363571 [Accessed 12.2.22]
- Chessa MA, Iorizzo M, Richert B, et al. Pathogenesis, clinical signs and treatment recommendations in brittle nails: a review. Dermatol Ther (Heidelb) 2020;10(1):15-27. doi: 10.1007/s13555-019-00338-x.
- Stern DK, Diamantis S, Smith E, et al. Water content and other aspects of brittle versus normal fingernails. J Am Acad Dermatol 2007;57(1):31-36. doi: 10.1016/j.jaad.2007.02.004.
- Egawa M, Ozaki Y, Takahashi M. In vivo measurement of water content of the fingernail and its seasonal change. Skin Res Technol 2006;12(2):126-132. doi: 10.1111/j.0909-752X.2006.00141.x
- DiBaise M, Tarleton SM. Hair, nails, and skin: differentiating cutaneous manifestations of micronutrient deficiency. Nutr Clin Pract 2019;34(4):490-503. doi: 10.1002/ncp.10321.
- Lipner SR, Scher RK. Biotin for the treatment of nail disease: what is the evidence? J Dermatolog Treat 2018;29(4):411-414. doi: 10.1080/09546634.2017.1395799.
- Colombo VE, Gerber F, Bronhofer M, Floersheim GL. Treatment of brittle fingernails and onychoschizia with biotin: scanning electron microscopy. J Am Acad Dermatol 1990;23(6 Pt 1):1127-1132. doi: 10.1016/0190-9622(90)70345-i.
- Floersheim GL. Behandlung brüchiger Fingernägel mit Biotin [Treatment of brittle fingernails with biotin]. Z Hautkr 1989;64(1):41-48. [Article in German]
- Hochman LG, Scher RK, Meyerson MS. Brittle nails: response to daily biotin supplementation. Cutis 1993;51(4):303-305.