Introduction
Hypertension is a debilitating cardiovascular condition that involves blood pressure levels rising to a dangerous threshold. It affects the quality of life of one billion people worldwide.1 While this condition is currently the most serious risk factor for death globally, it may be possible to mitigate the risk of developing hypertension via nutrition, as many foods have been found to possess heart-protecting properties. One such food is the dragon fruit, an exotic fruit grown in Mexico and Central America that has bioactives that promote health benefits in the form of anti-inflammatory and antioxidant effects.
What is hypertension?
As briefly mentioned in the introductory passage, hypertension is the condition of high blood pressure that remains consistently over a threshold of ‘healthy’ levels. This is categorised as blood pressure higher than 140/90mm Hg.1 Blood pressure is measured via the force of the blood flowing through the arteries. It is affected by how easily the blood is flowing through the arteries. Hypertension is a cardiovascular disorder, meaning it affects the heart and blood vessels primarily.
How can you check for hypertension?
Hypertension can often exist without symptoms in the earlier stages, making it a risk factor for more serious cardiovascular diseases such as stroke, heart attack or heart failure. It can also cause damage to the heart, brain and other vital organs if it is left untreated. The easiest way to determine whether you may have hypertension is to get a reading from a qualified practitioner, which will give a clear indication of your level of risk.2 As you can have high blood pressure and still function normally, it is important to check your blood pressure regularly to monitor any fluctuations and keep on top of your health.
You can ask for a blood pressure check at the following locations:2
- A general practitioner (GP) surgery - a GP, practice nurse, healthcare assistant or even a self-service machine
- A local pharmacy
- A hospital through an NHS Health Check appointment, which is offered to adults aged 40 to 74 in England
- Some workplaces
Hypertension risk factors
The exact cause of hypertension is not always clear and can vary from person to person. Some factors that can influence the likelihood of developing hypertension are the following:3
- Age - you are more likely to develop the condition as you become older
- A family history of the condition
- Diet - foods richer in cholesterol and saturated fats may deteriorate heart health and increase the pressure within the arteries.
- Alcohol intake levels - excessive consumption of alcohol greatly increases the likelihood of hypertension in the future.
- Weight and physical activity levels - obesity is a risk factor for hypertension.3
Symptoms of hypertension:
Some warning signs to watch out for that can indicate an increased blood pressure and risk of long-term hypertension issues are:3
- Headaches
- Difficulty breathing
- Chest pain
- Dizziness
- Nausea
- Vomiting
- Blurred vision or other vision changes
- Anxiety
- Confusion
- Buzzing in the ears
- Nosebleeds
- Abnormal heart rhythm
What is dragon fruit?
Dragon fruit is a tropical fruit that grows from a cactus plant, native to Mexico and Central America. The fruit is also called ‘pitaya’ in some regions of Central America.4 There are a few different types of dragon fruit, distinguished by the colour of the skin: white or yellow-skinned pitaya are milder, whereas the more commonly found red-pink varieties have a stronger flavour. Underneath the tough skin is a white flesh containing black seeds, and this flesh is typically the part that is consumed as it contains all the flavour and nutrients.
Vitamins and minerals in dragon fruit
There are numerous health benefits associated with the consumption of this striking fruit. According to the USDA's FoodData Central database, a 100g serving of dragon fruit delivers:5
- 16% of the daily intake of potassium, a mineral that aids in controlling the balance of fluids in the body, as well as helping your heart to beat at a consistent pace.5
- Magnesium is recommended for 10% of the daily intake and is known for its stress-reducing properties as well as its involvement in turning food into energy.5
- 8.5% of the recommended daily intake of vitamin C, known for its immune system boosting properties as well as its maintenance of healthy skin and blood vessels.5
- 2% of the daily recommended intake for folate, which is associated with healthy cell growth and function.5
Also, it is an ideal nutrient resource for those who are on a low-fat or low-sodium diet or simply wish to maintain a healthy and balanced diet, as the fruit contains zero levels of sodium and cholesterol and is low in fat.6
How can dragon fruit reduce the risk of hypertension?
Here are some potential ways that dragon fruit may help to reduce or prevent high blood pressure from arising:
- The vitamin and mineral profile of the dragon fruit is rich in essential heart-healthy compounds, which lower the risk of chronic diseases such as hypertension.
- Antioxidants such as polyphenols and flavonoids fight oxidative stress's effects and reduce inflammation across the entire body, including the heart. Studies in rats have found this protection of cells from damage to result in reduced systolic blood pressure levels as well as decreased oxidative stress.7
- Obesity is a key risk factor for hypertension. The combination of fibre and low-calorie content in dragon fruit makes it a highly effective aid in a weight-management programme. The high fibre content contributes to feelings of fullness while remaining low in calories and fat.
- Heart-healthy monounsaturated fats are found in dragon fruits, which help to maintain cardiovascular health.
While not many studies directly link human heart health and dragon fruit consumption, one British study on 19 healthy participants investigated the effects after consuming red dragon fruit powder daily for 14 consecutive days. They reported that their subjects showed significantly reduced pulse wave velocity, a measure of blood pressure.8
How to incorporate dragon fruit into your diet:
Dragon fruits are best eaten ripe. You can find dragon fruit year-round, but summer to early autumn is the best season for them. To choose one that is perfectly ripe and sweet, look for bright and even pink skin. A few marks on the outer skin are nothing to be concerned about, but dragon fruits with lots of spots on the flesh may be overripe. The skin should be a little soft and tender when you press it with your thumb, but not mushy.9 If the skin still feels too firm, you can always leave it to ripen further for a couple more days.
It is always useful to introduce new foods into your diet as it is interesting and fun, so the following are some creative ideas of how to add dragon fruit into your daily routine:
- Add it to fruit salads and fruit platters. It goes great alongside other tropical fruits like kiwi and papaya.
- Add it to breakfast bowls.
- Blend it into smoothies or other juice drinks.
- Make it into dragon fruit ‘ice cream’.
- Use it as the base of a dragon-fruit salsa.
Potential considerations and precautions
Overall, dragon fruit is a highly safe food to eat for the large majority of people. However, people may develop an allergic reaction on rare occasions after consuming the fruit. Two reports filed have shown that people assigned female at birth with no history of food allergies developed an anaphylactic reaction to eating dragon fruit, among some other fruits in a fruit mixture.10, 11
It is important to note that there have been only two official reports of reactions like this. It is unlikely to be a widespread issue. However, be cautious that you may be allergic to this fruit without knowing it.
Summary
Overall, many nutritious values of dragon fruit will undoubtedly contribute to improving cardiovascular health and potentially mitigate the risk of developing hypertension in the future. The fruit is simple to add to an existing diet and routine and can be added to many dishes or salads. Dragon fruit may contribute to a long-term healthy heart and overall health if eaten regularly, but as with any food, it should be consumed in moderation, i.e. not more than twice a day.
References
- Hypertension | what we do [Internet]. World Heart Federation. [cited 2023 Sep 27]. Available from: https://world-heart-federation.org/what-we-do/hypertension/
- nhs.uk [Internet]. 2017 [cited 2023 Sep 28]. High blood pressure (Hypertension) - Diagnosis. Available from: https://www.nhs.uk/conditions/high-blood-pressure-hypertension/diagnosis/
- Hypertension [Internet]. [cited 2023 Sep 27]. Available from: https://www.who.int/news-room/fact-sheets/detail/hypertension
- GrowVeg [Internet]. [cited 2023 Sep 27]. Dragon fruit grow guide. Available from: https://www.growveg.co.uk/plants/uk-and-europe/how-to-grow-dragon-fruit/
- nhs.uk [Internet]. 2017 [cited 2023 Sep 29]. Vitamins and minerals - Others. Available from: https://www.nhs.uk/conditions/vitamins-and-minerals/others/
- Fooddata central [Internet]. [cited 2023 Sep 29]. Available from: https://fdc.nal.usda.gov/fdc-app.html#/food-details/2344729/nutrients
- Anand Swarup KRL, Sattar MA, Abdullah NA, Abdulla MH, Salman IM, Rathore HA, et al. Effect of dragon fruit extract on oxidative stress and aortic stiffness in streptozotocin-induced diabetes in rats. Pharmacognosy Res. 2010 Jan;2(1):31–5.
- Cheok A, Xu Y, Zhang Z, Caton PW, Rodriguez-Mateos A. Betalain-rich dragon fruit (Pitaya) consumption improves vascular function in men and women: a double-blind, randomized controlled crossover trial. Am J Clin Nutr. 2022 May 1;115(5):1418–31.
- Real Simple [Internet]. [cited 2023 Oct 2]. How to eat dragon fruit like a pro. Available from: https://www.realsimple.com/food-recipes/cooking-tips-techniques/how-to-eat-dragon-fruit
- Damiani E, Aloia AM, Priore MG, Delle Donne P, Nettis E, Ferrannini A. ‘Allergy to red pitaya’. Allergy [Internet]. 2008 Sep [cited 2023 Oct 2];63(9):1252–3. Available from: https://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2008.01797
- Kleinheinz A, Lepp U, Hausen BM, Petersen A, Becker WM. Anaphylactic reaction to (Mixed) fruit juice containing dragon fruit. Journal of Allergy and Clinical Immunology [Internet]. 2009 Oct [cited 2023 Oct 2];124(4):841–2. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0091674909008161