Olive oil is synonymous with the Mediterranean diet, and the health benefits of both are well documented.

Olive oil reduces the risk of heart disease, cancer, diabetes and premature death. Olives also contain numerous healthy nutrients.

Now evidence is mounting about the health benefits of olive leaves, including from studies in a recent review.

Here’s what’s in olive leaves and who might benefit from taking olive leaf extract.

What’s in olive leaves?

Olive leaves have traditionally been brewed as a tea in the Mediterranean and drunk to treat fever and malaria.

The leaves contain high levels of a type of antioxidant called oleuropein. Olives and olive oil contain this too, but at lower levels.

Generally, the greener the leaf (the less yellowish) the more oleuropein it contains. Leaves picked in spring also have higher levels compared to ones picked in autumn, indicating levels of oleuropein reduce as the leaves get older.

Olive leaves also contain other antioxidants such as hydroxytyrosol, luteolin, apigenin and verbascoside.

Antioxidants work by reducing the oxidative stress in the body. Oxidative stress causes damage to our DNA, cell membranes and tissues, which can lead to chronic diseases such as cancer and heart disease.

Are olive leaves healthy?

One review and analysis combined data from 12 experimental studies with 819 participants in total. Overall, olive leaf extract improved risk factors for heart disease. This included healthier blood lipids (fats) and lowering blood pressure.

The effect was greater for people who already had high blood pressure.

Most studies in this review gave olive leaf extract as a capsule, with daily doses of 500 milligrams to 5 grams for six to 48 weeks.

Another review and analysis published late last year looked at data from 12 experimental studies, with a total of 703 people. Some of these studies involved people with high blood lipids, people with high blood pressure, people who were overweight or obese, and some involved healthy people.

Daily doses were 250-1,000mg taken as tablets or baked into bread.

Individual studies in the review showed significant benefits in improving blood glucose (sugar) control, blood lipid levels and reducing blood pressure. But when all the data was combined, there were no significant health effects. We’ll explain why this may be the case shortly.

Another review looked at people who took oleuropein and hydroxytyrosol (the antioxidants in olive leaves). This found significant improvement in body weight, blood lipid profiles, glucose metabolism and improvements in bones, joints and cognitive function.

The individual studies included tested either the two antioxidants or olive leaf incorporated into foods such as bread and cooking oils (but not olive oil). The doses were 6-500mg per day of olive leaf extract.

So what can we make of these studies overall? They show olive leaf extract may help reduce blood pressure, improve blood lipids and help our bodies handle glucose.

But these studies show inconsistent results. This is likely due to differences in the way people took olive leaf extract, how much they took and how long for. This type of inconsistency normally tells us we need some more research to clarify the health effects of olive leaves.

Can you eat olive leaves?

Olive leaves can be brewed into a tea, or the leaves added to salads. Others report grinding olive leaves into smoothies.

However the leaves are bitter, because of the antioxidants, which can make them hard to eat, or the tea unpalatable.

Olive leaf extract has also been added to bread and other baked goods. Researchers find this improves the level of antioxidants in these products and people say the foods tasted better.

Is olive leaf extract toxic?

No, there seem to be no reported toxic effects of eating or drinking olive leaf extract.

It appears safe up to 1g a day, according to studies that have used olive leaf extract. However, there are no official guidelines about how much is safe to consume.

There have been reports of potential toxicity if taken over 85mg/kg of body weight per day. For an 80kg adult, this would mean 6.8g a day, well above the dose used in the studies mentioned in this article.

Pregnant and breastfeeding women are recommended not to consume it as we don’t know if it’s safe for them.

What should I do?

If you have high blood pressure, diabetes or raised blood lipids you may see some benefit from taking olive leaf extract. But it is important you discuss this with your doctor first and not change any medications or start taking olive leaf extract until you have spoken to them.

But there are plenty of antioxidants in all plant foods, and you should try to eat a wide variety of different coloured plant foods. This will allow you to get a range of nutrients and antioxidants.

Olive leaf and its extract is not going to be a panacea for your health if you’re not eating a healthy diet and following other health advice.

Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, Accredited Practising Dietitian, University of South Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The World Health Organization (WHO) recently released new estimates suggesting around 846 million people aged between 15 and 49 live with a genital herpes infection.

That’s equivalent to one in every five people from that age group.

At least one person each second (42 million people annually) contracts a new genital herpes infection.

So what is genital herpes, and are cases on the rise? Here’s what to know about this common infection.

First, what causes genital herpes?

Genital herpes is a sexually transmitted infection (STI) caused by the herpes simplex virus, which also causes cold sores.

There are two types of herpes simplex virus, HSV-1 and HSV-2 (and it’s possible to be infected by both at the same time).

HSV-1 most commonly spreads through oral contact such as kissing or sharing infected objects such as lip balm, cups or utensils, and presents as cold sores (or oral herpes) around the mouth. But it can also be sexually transmitted to cause a genital herpes infection.

An estimated 3.8 billion people under the age of 50 (64%) globally have HSV-1.

HSV-2 is less prevalent, but almost always causes a genital herpes infection. Some 520 million people aged 15–49 (13%) worldwide are believed to have HSV-2.

The initial episode of genital herpes can be quite painful, with blisters, ulcers and peeling skin around the genitals over 7–10 days.

Not all people have severe (or any) initial symptoms. This means a person might not know they have been infected with a herpes virus.

Herpes is a lifelong infection, which means once you contract the virus, you have it forever. After an initial episode, subsequent episodes can occur, but are usually less painful or even symptom free.

Both oral and genital herpes are particularly easy to spread when you have active lesions (cold sores or genital ulcers). But even with no symptoms, herpes can still be spread to a partner.

And although relatively rare, oral herpes can be transmitted to the genital area, and genital herpes can be transmitted to the mouth through oral sex.

If an expectant mother exhibits a genital herpes infection close to childbirth, there are risks to the baby. A herpes infection can be very serious in a baby, and the younger the infant, the more vulnerable they are. This is also one reason why you should avoid kissing a baby on the mouth.

Changing trends

WHO’s recent figures brought together data from around the world to estimate the prevalence of genital herpes in 2020, compared with previous estimates in 2012 and 2016.

This data shows no significant difference in the prevalence of genital herpes caused by HSV-2 since 2016, but does highlight increases in genital herpes infections caused by HSV-1.

The estimated number of genital HSV-1 infections globally was nearly twice as high in 2020 compared with 2016 (376 million compared with 192 million).

A 2022 study looking at Australia, New Zealand and Canada found more than 60% of genital herpes infections are still caused by HSV-2. But this is declining by about 2% each year while new genital infections that result from HSV-1 are rising.

There’s no simple fix, but safe sex is important

Genital herpes causes a substantial disease burden and economic cost to health-care services.

With such a large proportion of the world’s population infected with HSV-1, evidence this virus is increasingly causing genital herpes is concerning.

There’s no cure for genital herpes, but some medications, such as antivirals, can help reduce the amount of virus present in the system. While this won’t kill it completely, it helps to prevent symptomatic genital herpes recurrences, improve quality of life, and minimise the risk of transmission.

To prevent the spread of genital herpes and other STIs, practise safe sex, particularly if you’re not sure of your partner’s sexual health. You need to use a barrier method such as condoms to protect against STIs (a contraceptive such as the pill won’t work). This includes during oral sex.

As herpes is now so common, testing is not usually included as part of a regular sexual health check-up, except for in specific circumstances such as during pregnancy or severe episodes.

So it’s wise not to let your guard down, even if your partner insists they have received the all-clear from a recent check-up.

If there are herpes lesions present around the genitals, avoid sex entirely. Even condoms are not fully effective at these times, as exposed areas can still transmit the infection.

Immune health

If you are infected with HSV-1 or HSV-2 it’s more likely symptoms will appear when you’re stressed, tired or overwhelmed. During these times, our immune system may not be as functional, and dormant viruses such as herpes can start to develop quickly in our bodies.

To reduce the risk of recurrent herpes infections, try to eat healthily, get at least seven hours of sleep each night if possible, and look out for when your body may be telling you to take a step back and relax. This self-care can go a long way towards keeping latent viruses at bay.

While the prevalence has increased significantly in recent years, we have not lost the war on genital herpes just yet. Safe sexual practices, education and awareness can help reduce its spread, and the stigma around it.

If you have personal concerns, you should discuss them with a medical professional.

Christian Moro, Associate Professor of Science & Medicine, Bond University and Charlotte Phelps, Senior Teaching Fellow in Medicine, Bond University

This article is republished from The Conversation under a Creative Commons license. Read the original article.