Refer a Friend and you both get a €3 gift voucher see here

Find out what your nails could be saying about your health

16 May 2024 • 0 min read

Whether you paint them, manicure them or just leave them be, your fingernails and toenails can reveal a lot about your health.

Did you know that brittleness or changes in colour could be hinting at an underlying condition? And is it true that white spots are a sign of calcium deficiency? Check out our rundown of nail health and the clues your nails could be hiding.

Brittle nails

As we age, our nails often become more brittle or crumbly. Exposing them to chemicals like nail polish or cleaning detergents, or even water, can also have the same effect. However, in some cases your nails could become brittle due to conditions like nail psoriasis, a fungal nail infection or an underactive thyroid or overactive thyroid. Lichen planus, an inflammatory skin condition can also cause brittle or split nails as well as zinc deficiency.

Discoloured nails

From grey to brown or red, look out for signs that your nails have changed colour to spot any underlying causes. Taking antimalarial medication can make nails look grey in appearance, whilst pregnancy or thyroid disease can result in brown nails. Under the nails, dark green or black patches tend to be caused by an overgrowth of bacteria while red or yellow blotches might be signs of nail psoriasis.

Dents on the nails

If you notice small dents on the surface of your nails, most of the time it could be a sign of inflammatory conditions like psoriasis, reactive arthritis or eczema. A less common cause is alopecia areata which results in temporary bald patches on the scalp.

Lines across the fingernails

Also known as Beau's lines, grooves or lines can form across the nail after exposure to cold temperatures, injuries or illness, and possibly cause slower nail growth. They may also be a result of chemotherapy, chronic alcoholism or a diet that is lacking in protein or zinc.

Thickened nails

A fungal nail infection, psoriasis and wearing shoes that are too tight or small often makes nails thicker or overgrown. Another cause is reactive arthritis, a condition that triggers swelling and redness in different parts of the body.

Tiny red or brown streaks

Known as splinter haemorrhages, damaged blood vessels under the nails can appear as tiny reddish streaks or lines. They are most likely the cause of nail injuries, but can also be a symptom of psoriasis, infections or autoimmune diseases like lupus.

Yellow nails

Fungal nail infections, nail psoriasis and regularly applying nail polish typically make your nails change colour. But that yellow hue could be down to several other, less obvious reasons. Nail discolouration can be caused by sinusitis, tuberculosis (TB), jaundice and conditions affecting the lungs or thyroid. In addition, medications like carotene can result in a yellowish tint.

White nails

As well as being a sign of fungal infection, your nail and nail bed turning white could be due to a condition called Terry’s nails. Terry’s nails normally appear red or darker around the edge and are caused by a reduction in blood supply to the nail bed. Medical conditions like diabetes, iron-deficiency anaemia and an overactive thyroid are common causes. But in most cases, damage to the liver, known as liver cirrhosis is the most widespread cause of Terry’s nails.

White spots

Normally not serious, white spots on the nails are most often caused by a knock or injury to the base of your nails. However in some cases fungal infections, mineral deficiencies or an allergic reaction can be to blame.

How can you prevent nail problems?

Looking after your nails

In many cases, taking the time to care for your nails is the best way to prevent conditions like nail psoriasis and keep other problems at bay. Keep nail edges smooth with a nail file and condition your cuticles and nails with a moisturiser or lotion, especially after they’ve been in water. If you work with your hands, wear gloves to protect them. For your feet, wear comfortable shoes that don’t put pressure on your toes.

Nutrients for your nails

Eating a balanced diet full of vitamins and minerals is key to maintaining your overall health as well as the health of your nails. Evidence1 has shown that Biotin supplements may help the condition of brittle nails. Having a diet lacking zinc has been linked to Beau's lines and brittle nails2, so it may be helpful to boost your intake of meat, shellfish and dairy products.

If you’ve noticed any changes to the texture, thickness or colour of your nails, tackle them quickly to make sure any abnormalities aren’t a sign of something more serious. If problems persist or you are concerned in any way, speak to your GP.


Shop our Vitamins & Supplements range.