Hydroxytyrosol is one of the key healthy-promoting compounds of the Mediterranean diet. Based on the research I reviewed, I feel like this nutraceutical hasn’t gotten the attention it deserves.

In this article, I’ll answer the following questions:

  • What is hydroxytyrosol?
  • What are the health benefits?
  • Are there any side effects?
  • How much should you take?

The Mediterranean Diet Paradox

Long before the Keto craze, or the vegan agenda, the Mediterranean diet was recognized as one of the healthiest diets.

Or, to be more accurate, the diet of some cultures living around the Mediterranean Sea was recognized as healthier. They experience better health and longevity than those living in many other parts of the world.

However, this reality has been perplexing for nutrition and health researchers. People eat high-fat foods, drink lots of wine, and even smoke cigarettes at higher rates than average. Yet, they live longer and suffer less disease.

There must be something in their diet or lifestyle that protects them from the lifestyle and nutrition choices that, according to “science” should kill them.

Mediterraneans eat a lot more olives and drink more wine than other cultures. As it turns out, these dietary staples contain some pretty powerful compounds:

  • hydroxytyrosol
  • resveratrol
  • melatonin

Red wine provides mainly resveratrol and melatonin, and a small amount of hydroxytyrosol. Olives, on the other hand, are the primary source of HT.

The fatty acids of olive oil promote brain health and prevent neurological disorders, inflammatory complications, and cancer.

Wani TA, et al. 

Regular consumption of olives, or more precisely, the fatty acids in olives, is associated with:

  • Lower risk of neuropsychiatric disorders
  • Lower risk of lateral sclerosis
  • Better motor coordination
  • Prevention of osteoarthritis, when combined with exercise
  • Prevention of atherosclerosis
  • Relief of symptoms of colitis

These health benefits aren’t necessarily from the fatty acids in olive oil. They’re from the hydroxytyrosol.

What is hydroxytyrosol?

Hydroxytyrosol (HT) is a polyphenol found in olive fruits and olive leaves. It’s also found in red wine, although the concentration is much lower than in olives. Along with another compound in olives, oleuropein, HT gives extra-virgin olive oil its distinctive taste.

Extraction of HT from olives usually requires solvents like methanol and hexane. However, it is possible to extract HT with water alone. When choosing a supplement, I’d recommend using only hydroxytyrosol extracted with water. It eliminates the possibility of any leftover solvents from ending up in your system.

Hydroxytyrosol is rapidly absorbed in the small intestine and reaches peak blood levels within 5-10 minutes.

Hydroxytyrosol is the only phenolic compound that is able to cross the blood-brain barrier, which allows it to also absorb free radicals throughout the central nervous system.

Ziosi P, et al.

When you metabolize the neurotransmitter dopamine, you produce a modest amount of hydroxytyrosol. Diseases that lower dopamine levels, such as depression, schizophrenia, psychosis, and Parkinson’s, would also cause very low levels of hydroxytyrosol.

As a supplement or nutraceutical, it’s essential to take it with fat. The fat enhances its absorption.

What are the health benefits?

As I researched hydroxytyrosol for this article, I found a dizzying number of research-supported health benefits. Much of the research is based on cell cultures and animal studies. Some is based on research in humans.

When you combine the scientific evidence with what’s seen in population-based research of Mediterranean people, you end up with a pretty convincing argument in favor of increasing HT consumption.

Mitochondrial and Metabolic Function

Your life depends on your mitochondria, teeny-tiny power plants found in almost every cell of the body. Most known diseases result in some kind of dysfunctional mitochondria.

Hydroxytyrosol enhances mitochondrial function, and may stimulate mitochondrial biogenesis.

Mitochondrial biogenesis is the growth of mitochondria. As they get bigger, or increase in number, you’re able to produce more energy.

As mitochondrial function improves, fat metabolism increases and insulin sensitivity is restored. Research shows hydroxytyrosol may also prevent adipogenesis, the growth of new and larger fat cells.

With all that said, don’t assume you can just supplement with hydroxytyrosol while you continue eating junk food, avoiding strength training, and live in sleep debt, and expect your health to be restored.

If you’re interested in long-lasting health, you’ll make The First 3 Habits of VIGOR(ESS) Health nonnegotiables. HT supplementation is in addition to the first three habits, not in place of any of them.

Altogether, these findings suggest that HT might be an effective agent for the prevention and treatment of diabetes and metabolic syndrome, but more clinical trial[s] should be performed to determine by which mechanisms the HT can act against metabolic syndrome.

Robles-Almazan M, et al.

Skin health

Though some sun exposure is important for your mental and physical health, too much can cause damage to the DNA of your skin cells. The excessive sun might help you get more vitamin D, but you’ll look like you’re wearing a costume made of dehydrated mangos.

Hydroxytyrosol acts as a potent antioxidant for the skin, and helps protect it from sun damage. It may even help slow the aging of your skin.

Fetal Development

Maternal stress can cause motor and cognitive dysfunction in a developing baby, and an altered response to stress as the baby matures.

Though it’s best to minimize stress while pregnant, animal research shows hydroxytyrosol can protect the nervous system of a developing fetus from the effects of some stress.

…our study demonstrates that prenatal stress can reduce mitochondrial content and anti oxidative capacity and increase oxidative stress in the hippocampus of offspring, contributing to decreased neurogenesis and cognitive function. Maternal HT administration successfully promotes cognitive function through modulation of mitochondrial content and phase II enzymes.

Zheng A, et al.

Cardiovascular Health

The effects of hydroxytyrosol on cardiovascular health, or more precisely, the effects of the Mediterranean diet on cardiovascular health, is what first led researchers down the path of investigating olives, olive oil, and HT.

Hydroxytyrosol has numerous, positive cardiovascular effects in the body.

Research shows it:

  • enhances mitochondrial function and fat metabolism
  • helps restore insulin sensitivity
  • supports healthy cholesterol and triglyceride levels
  • combats the oxidation of LDL cholesterol
  • supports normal inflammation levels
  • inhibits platelet aggregation, which reduces the risk of a blood clot

Each of these effects improves overall cardiovascular health, and helps reduce the risk of a cardiovascular event.

Bone and Joint Support

Hydroxytyrosol may slow the loss of bone density common with age or joint immobilization.

It may also protect bone density from damage by acrolein, a chemical found in cigarette smoke. Acrolein damages osteoblasts, the cells that produce your bone matrix.

Because HT also supports normal inflammatory levels, it may slow the progression of certain types of arthritis as well.

Nervous System Function

Nervous system dysfunction can cause significant physical and cognitive problems. Some degenerative diseases, like Parkinson’s and diabetic neuropathy, are caused by oxidation in the nervous system.

Research shows hydroxytyrosol may slow the progression of these diseases by curbing oxidation. To what extent remains to be seen, as most of this research has been with animals.

Some hydroxytyrosol is produced in the body through the metabolism of dopamine. Unfortunately, many nervous system diseases cause lower dopamine levels, which then lower HT levels as well. In this regard, HT is considered neuroprotective.

Supports Detoxification

Hydroxytyrosol plays a role in phase II detoxification. It may also help preserve glutathione levels.

Endurance Exercise Capacity

Since HT enhances mitochondrial function and fat metabolism, it’s little surprise that it also seems to improve endurance capacity.

By generating more aerobic fuel, more efficiently, it could provide some ergogenic benefit. That said, there’s been very little research to test this out, especially in humans.

I won’t be much help with personal experience here, since I don’t do cardio, and stick to mainly strength training.


Cell studies of hydroxytyrosol and cancer show promise. HT has been studied with leukemia, colon cancer, breast cancer, liver cancer, and skin cancer.

However, the effects of a treatment in a cell culture doesn’t always translate to benefits inside the body. At this point, there isn’t evidence it would help, but there’s plenty of evidence to show it wouldn’t hurt.

What are the contraindications?

HT has a strong safety record.

The only potential medication-related concerns identified relate to diabetes and high-blood pressure.

Hydroxytyrosol may have a blood sugar or blood pressure lowering effect. For those on medication for diabetes or hypertension, talk to your doctor first. It’s possible that your medication may need to be adjusted to avoid lowering levels too much.

How much should you take?

To achieve any therapeutic benefits, a minimum dose of 5 mg per day was recommended by the European Food Safety Authority (EFSA), although that’s a pretty low amount. 

Some research has shown a dose of 15 mg produces significant effects, while other studies have used 30 mg per day in adults.

The most significant benefits likely come from regular, long-term use. A reasonable dose of 20 mg per day, consumed through food or supplements, would probably be sufficient.

Also, hydroxytyrosol is extremely safe. Animal studies have used as much as 2g/kg body weight to test its toxicity, with no ill effects. That’s about 150 grams for a 150 pound person, a ridiculous amount.

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[bg_collapse view=”link” color=”#3578e5″ state=”closed” expand_text=”Show References” collapse_text=”Hide References” ]

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EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Scientific opinion on the substantiation of health claims related to polyphenols in olive and protection of LDL particles from oxidative damage (ID 1333, 1638, 1639, 1696, 2865), maintenance of normal blood HDL-cholesterol concentrations (ID 1639), maintenance of normal blood pressure (ID 3781), “anti-inflammatory properties” (ID 1882), “contributes to the upper respiratory tract health” (ID 3468), “can help to maintain a normal function of gastrointestinal tract” (ID 3779), and “contributes to body defenses against external agents” (ID 3467) pursuant to Article 13(1) of Regulation (EC) No 1924/20061. EFSA J. 2011;9(4):2033.

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