Some health problems can be very sneaky — they may look like something simple and not alarm you enough to feel compelled to check it out, at least in the early stages. Doctors say that the earlier people find out about issues, the easier the treatment will be, and in some cases, early diagnoses may actually save your life.

We at Bright Side believe that it is important to tell our readers about symptoms that might be indications of something very serious. Just in case.

1. A scalloped tongue

scalloped tongue is a situation where the tongue’s edges look like a pie crust and, basically, it means that the tongue is becoming larger than the lower jaw. Unless you had a jaw trauma, this condition is normally caused by swelling. The swelling can be the result of a few things, and some can be easily fixed without visiting a doctor like, for example, dehydration.

However, if you’re also experiencing other symptoms, like aches, cramps, hair loss, low blood pressure, and bruising, it might be a sign of a thyroid disorder.

2. Black lines on nails

Nails can often tell a lot about our health. Some people naturally have very thick or thin nails but if you notice any change in their structure or color, you should get it checked. Dark vertical lines are one of them and they can be a sign of melanoma. If you don’t recall hurting your nail or don’t have another obvious explanation as to why it might be bleeding or don’t know what caused the dark line, it should certainly be checked by a specialist.

3. Darkening and thickening of the skin

If you notice brown or yellow patches, that are slightly swollen and that feel like velvet, appear on the areas where your skin folds, under the armpits or neck, don’t ignore this. It might be a sign of insulin resistance and you definitely should get this checked out sooner rather than later. This can be part of a condition where the body doesn’t respond to insulin the way it should and might lead to type 2 diabetes.

4. Pimples on the jawline and chin

Under the skin, we have lots of tiny glands that produce natural oils to keep our skin in good condition, and these oils move up through the pores. When, for some reason, these glands make more oil than our skin can handle, the pores get clogged. For women, getting pimples along the jawline can be a sign of a hormonal imbalance — when too much of the male hormone, testosterone, gets produced it stimulates these oil glands.

5. Thinning eyebrows

As people age, they experience natural hair loss, but thinning eyebrows can be a sign of hypothyroidism, a thyroid condition. If the thyroid gland doesn’t work properly, it might produce too much or not enough of a particular hormone, and both of these conditions cause thinning hair on the body. We lose hair all the time, it’s a natural process, but new regrowth is supposed to replace it. When hormone production is unbalanced, it affects the developing new hair at its root and the hair that fell out doesn’t get replaced.

6. A pimple that doesn’t heal

We all get pimples every now and then. Some of us are more lucky than others, but normally pimples are caused by clogged pores. However, if you get a small “pearly” pimple that just doesn’t go away for weeks and easily starts bleeding, you should check it out since it might be a sign of a basal cell carcinoma. Although it sounds scary, this type of skin cancer is the least risky, it doesn’t spread, and can be treated relatively quickly, especially if it’s diagnosed early.

7. Unusual hair growth for women

If hair suddenly starts to grow in a male area, like above the lips, around the chin, or below your belly button, it could be a symptom of a polycystic ovarian syndrome (PCOS) when ovaries get enlarged as a result of a hormonal imbalance. Keep in mind that genetics can be a reason as well, so check the photos of your relatives first.

8. Finger pain

Thickened, sensitive fingers can be a sign of lung cancer. When lung tumors develop, they release some chemicals into the bloodstream that stimulate tissue growth under the fingernail and in the fingertips, causing pain. If you experience thickening and swelling on your fingers, check it out, it’s always better to be safe than sorry.

9. Yellowing of the skin and the whites of the eyes

A yellow color on the skin or the eye whites is a common skin symptom for liver issues. The eyes usually turn yellowish because a chemical called bilirubin accumulates in the blood. You should definitely visit a doctor as soon as you notice the yellow color, since an early diagnosis can prevent serious health complications.

10. Dark undereye circles

Dark undereye circles are normally the result of lifestyle issues. When we don’t get enough sleep, have a poor diet, or an unhealthy lifestyle, the fat tissue around our eyes changes and our skin becomes thinner. Although these dark spots generally don’t require medical attention, it’s a message for you that you should be taking better care of yourself.

Do you know about any other signs that can alarm you about possible health issues? Tell us about them in the section below.

Illustrated by Leonid Khan for Bright Side