Hibiscus and Heart Health.
During some start of the year tidying I found a jar of the Happy Heart tea I make. As a result of being low on the tea stocks (shameful I know) I thought I would make myself a cup of tea. I remember how much I love this blend and my love for hibiscus. Hibiscus is one of 4 herbs in my Happy Heart tea blend. I love the sour taste and what it does for heart health. High blood pressure is a major risk factor for stroke and a contributor to heart disease. Hibiscus is excellent for mild or moderate hypertension.
Hibiscus and Hypertension.
Estimates are that 7 million people in Canada suffer from hypertension. Roughly 20% of these people do not know that their blood pressure is high. Over a million people unaware that their health is at risk. Without explicit signs and symptoms hypertension is called the silent killer, because frequently there are no outward signs/symptoms of high blood pressure. Damage, however, is happening in the heart, kidneys, brain, and blood vessels. You don’t know you have it until the damage is done.
Blood pressure readings are made up of 2 numbers – expressed as a ratio. 120/80 for example. The top number (systolic) measures the blood pressure as your heart contracts – outgoing force. The bottom number (diastolic) measures the pressure as your heart relaxes.
Low risk 120/80
Medium risk 121-134/80-84
High risk 135+/85+
Over time, as blood flows through the cardiovascular system at high pressure, physical changes happen. Under relentless pressure blood vessels thicken and become smaller. They lose elasticity and become rigid. This loss of elasticity leads to – higher blood pressure. Imagine it this way – you start with blood vessels the size of rigatoni and you end up with blood vessels the size of penne, as a result it is harder to get blood to the tissues. You have to pump it through a tiny tube when it should be a large tube.
Physical Damage.
In the face of these changes the heart has to work harder. The heart is a muscle. When we work a muscle harder over time? It enlarges. High blood pressure typically causes the left ventricle to enlarge – hypertrophy. Thickened heart muscle is harder to pump.
Sustained high blood pressure causes damage to the blood vessels themselves. Years ago I worked in theatre. In one show an actress repeatedly kicked the drywall in the back wall of the theatre. Over the course of the run she kicked a hole in the drywall. Repeated high blood pressure causes tiny tears in the vessel. Plaques can form in the tears as the body tries to repair the damage.
Hibiscus Help.
Hibiscus lowers blood pressure. It also lowers levels of LDL and improves HDL. It has been used as a weight loss tea. I thought this was a function of the plant’s action as a diuretic (not real weight loss imo) but reading recent studies there is another mechanism of action that leads to weight loss. Hibiscus has been used for urinary tract infections. It is a diuretic and antimicrobial. Most urinary tract infections are E. coli and hibiscus is active against E. coli. Hibiscus is potassium sparing as a diuretic.
Hibiscus
When we see that blood red colour of the hibiscus, we know we are looking at anthocyanins. These plant pigments are antioxidants. Anthocyanins help dilate arteries and prevent plaque buildup. They lower blood viscosity – making it easier for blood to flow freely in the circulatory system. Hibiscus is high in a flavonoid called rutin. Rutin is antioxidant, anti-inflammatory, strengthens blood vessels and improves blood circulation. Hibiscus acts to increase nitric oxide. Nitric oxide relaxes vascular tissue and inhibits platelet aggregation. The plant also acts as an ACE inhibitor. Angio-tension converting enzyme produces angiotensin ll which narrow blood vessels. ACE inhibitors block the activity of this enzyme – relaxing blood vessels to lower blood pressure. Many pharmaceuticals prescribed for hypertension act because they are ACE inhibitors.
Hibiscus Botany.
Hibiscus (Hibiscus sabdariffa) is a member of the Malvaceae family – like marshmallow, okra, mallow, cotton, and linden. I think we should have wanted posters for plants and list their aliases underneath. Hibiscus is known as asam bylanda, bissap, Florida cranberry, Guinea sorrel, Indian sorrel, Jamaican sorrel, java jute, jelly okra, karkade, luo shen hua, pink lemonade, Queensland jelly plant, red sorrel, ribena plant, roselle, rose-mallow, rose of Sharon, rozelle hemp, sour-sour, sour tea, and zobo.
Hibiscus grows throughout tropical and subtropical regions. It is a tropical plant native to Africa. A perennial in zones 10-12 the plant is an annual in temperate climates. The plant grows anywhere from 6 to 8 feet tall in the tropics. In temperate climates it will be smaller. White to yellow flowers. The leaves are alternate, with lobed lower leaves. The plant can be grown as an annual in Ottawa – it needs full sun and good drainage.
Medicinal Usage.
The part of the hibiscus plant used is the calyx. Many people think that they are working with the flowers, but they aren’t. I checked online herb suppliers and almost without exception they list their hibiscus as hibiscus flowers. A calyx is a collection of the sepals of a plant. Sepals act to protect the developing flower. Harvest hibiscus after the flowers have died back. It can take 11 pounds of fresh hibiscus to make 1 pound of dried hibiscus. As much as I love hibiscus, I don’t see myself fighting with the Ottawa growing season to grow it myself. The calyces are rich in vitamin c, thiamin, beta carotene, niacin, and riboflavin. Hibiscus is photoperiodic – the plant flowers in response to the shortening or lengthening of the days. In the case of hibiscus, the plant flowers in the fall as the days shorten.
Heart Healing.
Drink Hibiscus.
I suggest making a decoction of hibiscus. 10 g of hibiscus per 500 ml water. Decoct for 10 minutes at 100 degrees, strain and drink during the day. If you didn’t want to make a decoction, I think an extended steeping period would be almost as good.
Don’t take hibiscus in conjunction with pharmaceuticals prescribed for high blood pressure. Take it at least 3 hours away from when you take acetaminophen.
If you are local to Ottawa the awesome Dominion City Brewery has a hibiscus beer that they are featuring.