Have you ever noticed that you seem to bruise more easily than others? Maybe you wake up with a mysterious black-and-blue mark and have absolutely no idea how it got there. Even more frustrating, bruises tend to go through an entire color spectrum—red, blue, purple, green, and yellow—none of which are particularly flattering.

While most bruises are harmless and often caused by minor bumps you don’t even remember, they can sometimes be painful or slow to fade. In certain cases, frequent or unexplained bruising may be a subtle signal that something deeper is happening inside your body.

Let’s take a closer look at why bruising occurs, when it’s considered normal, when it might be a cause for concern, and which vitamin deficiencies can make bruises appear more easily and more often.

So, What Exactly Is a Bruise?

The medical term for a bruise is ecchymosis, which is about as unpleasant-sounding as the bruise itself looks. A bruise forms when tiny blood vessels—called capillaries—break beneath the skin. Blood then leaks into the surrounding tissue, but unlike a cut or scrape, it doesn’t escape the body. Instead, it pools under the skin, causing discoloration.

Bruising usually follows some form of minor trauma, such as:

• Bumping into a table or countertop

• Knocking your shin on the bed frame

• Brushing your arm against a doorframe

• Having blood drawn during a medical test

Even if you don’t remember the moment of impact, the bruise will eventually make itself known. It typically starts out dark blue, purple, or red and gradually changes color as your body breaks down and reabsorbs the trapped blood. This color change is a normal part of the healing process and usually takes one to two weeks.

When Bruising Is (Probably) Nothing to Worry About

Most bruises appear on areas like the arms and legs and fade on their own within a couple of weeks. In these cases, bruising is generally considered normal and harmless.

That said, it’s a good idea to talk to a healthcare provider if you notice any of the following:

• Bruises appearing on unusual areas such as the stomach, back, buttocks, genitals, ears, or hands

• Bruises occurring very frequently or increasing over time

• Bruises that don’t change color or show signs of healing

• Bruises that last longer than two weeks

• Bruises that appear without any injury you can recall

These patterns don’t automatically mean something serious is wrong, but they do warrant a closer look.

How Vitamin Deficiencies Can Affect Bruising

Vitamin deficiencies can show up in unexpected ways. While deficiencies in vitamin D or B vitamins often get attention, easy bruising is commonly linked to shortages in two other key nutrients: vitamin C and vitamin K.

1. Vitamin C Deficiency

Vitamin C does far more than support your immune system. It’s essential for producing collagen, a structural protein that helps keep your skin, tissues, and blood vessels strong. Without enough collagen, capillaries become weaker and more prone to breaking—even from very mild pressure.

Low vitamin C levels can lead to:

• Increased bruising

• Bruises forming from minimal contact

• Slower wound healing

People who smoke, experience poor appetite, or eat few fruits and vegetables are especially at risk of vitamin C deficiency.

Good sources include: citrus fruits, strawberries, kiwi, tomatoes, bell peppers, broccoli, and leafy greens. Supplements may be helpful when dietary intake is low.

2. Vitamin K Deficiency

Vitamin K plays a critical role in blood clotting. When levels are low, blood doesn’t clot as efficiently, making it easier for bruises to form and harder for them to resolve.

In addition to clotting, vitamin K helps maintain strong capillary walls, reducing the likelihood of blood vessel damage in the first place.

Signs of low vitamin K may include:

• Frequent bruising

• Easy bleeding

• Bruises that spread or linger

Good sources include: leafy green vegetables such as spinach, kale, Swiss chard, broccoli, Brussels sprouts, and certain vegetable oils.

Final Thoughts

Occasional bruising is a normal part of everyday life. But if you’re noticing bruises more often than usual, in unusual locations, or without any clear cause, your body may be sending you a message worth paying attention to. In some cases, the solution can be as simple as improving your diet, correcting a vitamin deficiency, or making small lifestyle changes.

When in doubt, it’s always best to consult a healthcare professional—especially if bruising is persistent, worsening, or accompanied by other symptoms. Your skin can reveal more about your health than you might think.