KEY TAKEAWAYS

  • Milk thistle may help lower LDL cholesterol and raise HDL.
  • Works best when combined with diet, exercise, and medical care.
  • Supports liver health, brain protection, and acne reduction.
  • Generally safe but not recommended for everyone.
Medium shot man with chest pain

If you've been told to watch your cholesterol, you're not alone. High cholesterol affects millions and it often comes with no symptoms.

While medications and diet changes are the usual go-to, some people look to herbs for added support. One of the most talked-about options? Milk thistle, a spiky purple-flowered plant with deep roots in traditional medicine.

Many know milk thistle for its liver-protective effects. But today, researchers are also looking at the link between milk thistle and cholesterol. Could this herb do more than we think?

What Is Cholesterol and Why Does It Matter?

Cholesterol is a fat-like substance found in your body and certain foods. Your liver makes all the cholesterol you need. The rest comes from animal-based foods like meat, eggs, and dairy.

Cholesterol isn’t always bad. Your body uses it to build cells, hormones, and vitamin D. But too much can be harmful.

There are two main types of cholesterol:

  • LDL (Low-Density Lipoprotein): This is the “bad” kind. It can build up in your arteries.
  • HDL (High-Density Lipoprotein): This is the “good” kind. It helps remove extra cholesterol from your blood.

When LDL cholesterol builds up in the arteries, it creates plaques. This narrows the arteries and makes them stiff.

This condition, called atherosclerosis, raises your risk for heart attacks and strokes. That’s why managing cholesterol is so important.

Causes of High Cholesterol

Most people with high cholesterol have no clear symptoms. You won’t feel it building up in your arteries.

That’s why doctors recommend regular blood tests, especially after age 20.

1. Eating Too Much Saturated and Trans Fat

Saturated and trans fats are the biggest dietary culprits when it comes to high LDL (bad) cholesterol. Over time, the excess LDL cholesterol sticks to your artery walls. It forms thick, sticky deposits called plaques. These plaques narrow your arteries and make it harder for blood to flow.

Think of it like a kitchen drain: when too much grease builds up, it clogs the pipe. In your body, clogged arteries can lead to heart attacks or strokes.

2. Lack of Physical Activity

Exercise helps your body raise HDL (good) cholesterol and lower LDL.

When you don’t move enough:
- LDL cholesterol stays in the blood longer
- Fat builds up more easily in the arteries
- Blood flow becomes less efficient

3. Being Overweight or Obese

Extra weight (especially around the belly) will raise your risk of high cholesterol. It also increases triglycerides, another type of fat in the blood that can worsen heart health.

Fat cells release chemicals that trigger inflammation and make it harder for the body to clear LDL. This will disrupt the liver's cholesterol control system

4. Smoking

Smoking damages the lining of your arteries. This damage allows cholesterol to stick more easily to the artery walls.

5. Diabetes or Insulin Resistance

When blood sugar levels are too high for too long, the LDL cholesterol becomes smaller and more dense, which makes it more dangerous. This increases the chance that fats will collect in the arteries and block blood flow to the heart and brain.

6. Family History and Genetics

Some people are born with genes that cause their bodies to make too much cholesterol. This condition is called familial hypercholesterolemia.

How Milk Thistle and Cholesterol Related

Milk thistle (Silybum marianum) is a plant known for its strong antioxidant properties. The active compound in milk thistle is called silymarin.

Silymarin may protect cells from damage, reduce inflammation, and support liver function. But it may also have important effects on cholesterol levels.

In a clinical trial, people with Type 2 diabetes took silymarin for six weeks. Their LDL cholesterol went down, and so did their blood sugar. This study showed silymarin can improve both cholesterol and glucose control.

Another study tested a combo of milk thistle and Indian barberry (Berberis aristata). The results? Lower LDL cholesterol and better blood sugar balance. This supports using milk thistle and cholesterol as part of a natural health approach.

Why Silymarin Matters

Silymarin is lipophilic, meaning it dissolves in fat. It attaches to cell membranes and helps strengthen them. This helps prevent cell breakdown and reduces the build-up of bad fats in the blood.

Animal studies also back this up. In one, milk thistle stopped fatty plaque from forming in the aorta (the body’s largest artery). This suggests milk thistle and cholesterol are closely linked, especially in preventing atherosclerosis.

SUMMARY

Silymarin also helps reduce how much cholesterol your intestines absorb. At the same time, it increases how much cholesterol your liver breaks down. Together, these actions help lower total cholesterol levels in the blood.

Other Milk Thistle Plant Benefits

Besides milk thistle and cholesterol, the plant benefits reach other parts of the body.

1. Supports Liver Health

Milk thistle is commonly used by people with liver damage from alcohol, fatty liver, or hepatitis. Studies show it may reduce liver inflammation and improve enzyme levels in people with non-alcoholic fatty liver disease (NAFLD).

2. May Protect the Brain

Silymarin has strong antioxidant and anti-inflammatory effects. In animal studies, it protected brain cells from age-related damage. This may help slow down memory loss and cognitive decline.

3. May Help with Acne

Oxidative stress in the body may cause acne. In one study, people who took 210 mg of silymarin daily for 8 weeks saw a 53% drop in acne breakouts.

Is Milk Thistle Safe?

Milk thistle is generally safe when taken as a supplement. Most people have no side effects. If side effects do happen, they are usually mild including bloating, nausea and diarrhea.

But some people should be cautious:

  • Pregnant women: Safety is not confirmed
  • People with diabetes: It can lower blood sugar too much
  • Those allergic to plants in the daisy family: It may cause allergic reactions
  • People with hormone-sensitive conditions: Milk thistle can act like estrogen and may make symptoms worse

Always talk to a healthcare provider before starting any new supplement, especially if you're taking medications.

Final Thoughts

If you're looking for a natural way to support your heart health, milk thistle might be worth considering. Studies show that it can lower LDL, raise HDL, and reduce how much cholesterol your body absorbs. It may even help prevent artery plaque from forming.

But remember, milk thistle and cholesterol management go hand in hand with other healthy habits. Use it as a support and not a substitute for diet, exercise, and medical treatment.