Health is a complicated matter, and sometimes problems in one part of your body show up as symptoms in another part. Or, an illness in your whole body only shows up as an obvious symptom in only one part. You might get a headache when your whole body is dehydrated. You might have breathing problems or a swollen tongue after getting stung by a bee on the foot. You can even have an increased risk of heart disease from having gum disease.
Your skin is no different. Many skin related symptoms, like itchiness or redness, have simple explanations, like external irritants. But sometimes, they are a sign that something is going on inside your body.
Your skin does not function in isolation
Skin is the body’s largest organ, and the most visible indicator of overall health. It doesn’t just act as a protective layer (although it does that too); it works in tandem with your body’s internal processes. Your skin is supplied with blood by tiny blood vessels, or capillaries, all over your body, from which it receives the nutrients it needs to look and feel healthy.
Capillaries also carry away waste, like carbon dioxide, so it doesn’t build up in your skin. These tiny blood vessels are connected to the rest of your circulatory system which works with your whole body. When other systems in your body start to malfunction, it can affect the way your skin looks.
Most people are familiar with the connection between acne and hormones, or even the way someone can look pale when they have a cold or flu. These are only a couple of examples of how internal issues affect skin. But, changes in your skin can also indicate more serious or chronic health issues. Often this is because your body is using more energy and resources to fight illness, but the skin might also be reacting to harmful substances produced from diseased tissues, like bacteria or inflammatory molecules.
How to know when skin changes signal health problems
It’s important to note that only a doctor can tell for certain that your skin problems are related to internal diseases (and usually they aren’t). But there are some signs that indicate you might want to see a board-certified dermatologist to figure out what’s going on. Some internal diseases can manifest skin symptoms like:
Rashes and unexplained itchiness
If you have a rash without a known cause (like poison ivy) or that doesn’t go away, it could be a sign of something deeper.
For example, lupus, an autoimmune disease, often causes a butterfly-shaped, red rash on the face. Chronic, intense itching (pruritus) without an obvious rash, or a bumpy rash called lichen planus, can indicate liver disease or chronic kidney failure. Thyroid disorders can also cause itchy, dry, or discolored skin that might seem like a rash.
Skin thickening
A dark, velvety thickening of the skin on the neck or underarms (called acanthosis nigricans) might be linked to insulin resistance, which is a precursor for diabetes. Some forms of skin thickening can be caused by internal cancers, particularly gastrointestinal, prostate, breast, and ovarian cancers.
Thick, hardened skin can also be caused by an autoimmune condition called scleroderma. Scleroderma causes excessive collagen production, leading to fibrous, stiff tissue in the skin and other organs. Skin involvement often indicates internal organ involvement.
Redness
Redness is often a normal reaction to an itch, pressure from an object pressing against it, or an irritating substance or bug bite. But, if your skin stays red for a long time or it happens often for no obvious reason, it could warrant further investigation.
Redness of the skin usually indicates inflammation, especially if the skin feels warm or like it’s burning. Redness is sometimes accompanied by bumps. There are many causes of inflammation, both external and internal. Many internal diseases cause inflammation in the body that can show up in the skin. Persistent skin redness can sometimes be caused by autoimmune disorders, like lupus or dermatomyositis, various types of cancer, a severe infection, and gastrointestinal conditions.
Discoloration
While discoloration is due to aging and sun exposure, some forms of discoloration are from internal functions. For example, white patches may be vitiligo, which is a loss of skin pigment due to an autoimmune condition linked to thyroid disease or type 1 diabetes. An overall yellow look to your skin (jaundice), on the other hand, might indicate a problem with your liver or gallbladder.
Growths
Some internal issues can result in growths on the skin that can be anything from a large nodule to a waxy flat bump. Occasionally, a sudden eruption of many brown or black growths, called seborrheic keratoses, can be a sign of internal cancer, although seborrheic keratoses are usually benign. Nodules growing on this skin can also be a sign of various cancers, infections, or autoimmune disease.
How dermatologists know when the problem is more than skin deep
Dermatologists are trained to know what your skin says about your health, and they’ve seen it all. Since there are often many possible explanations (and it’s very easy to assume the worst) when you have a new skin issue, it’s best to let a board-certified dermatologist do a proper examination to determine the cause.
When you go in for an appointment for an unexplainable skin issue, the dermatologist will take a close look and ask several questions about how long you’ve been experiencing symptoms (like itchiness, discoloration, thickening, etc.). If it is not something they can quickly diagnose (like eczema or rosacea), they will likely ask whether you are experiencing any non-skin related issues, like fatigue, headaches, or anything out of the ordinary. Additional symptoms can help them link the skin problem to potential internal illnesses.
From there, the dermatologist might take a biopsy, order blood tests, or, if they strongly suspect a specific internal problem, they might refer you to a specialist that deals with that issue. For example, if your dermatologist determines that you have the butterfly-shaped rash associated with lupus, they might refer you to a rheumatologist.
If you work with a board-certified Forefront dermatologist, they will have the support of Forefront’s dedicated dermatopathology lab for most tests. As a laboratory dedicated exclusively to skin, our lab can bring specialized expertise and exceptional care to every diagnosis made. And being one of the largest dermatopathology labs in the country means rare and complex pathology is part of everyday practice for our dermatopathologists.
Results from our rigorous lab tests can help a dermatologist rule out or diagnose many internal diseases. Once internal illnesses are ruled out, they will most likely treat your problem as a skin issue and provide treatment or advice.
If you’re uncertain about a skin change—start with a dermatologist
It can be hard to know when skin changes signal health problems—and health isn’t something you want to guess at. The best way to find out if changes in your skin mean something is off in your body is to go to a board-certified dermatologist. At Forefront, we know skin health is an important part of overall health. If you want to know what your skin is saying about your overall health, find a Forefront location near you and book an appointment with one of our board-certified dermatologists.
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