High blood pressure affects 25% of adult South Africans, with black African people appearing to be more susceptible than other groups. Experts suggest this may have a lot to do with the high levels of salt in our diets and that reducing this excessive consumption might be an effective, easy way of helping to protect ourselves from this devastating condition.
High blood pressure is a grave health concern in South Africa. Local studies suggest that one in every four South Africans between the ages of 15 and 64 already suffers from the condition - and that this number is rising rapidly.
Black South Africans appear to be more at risk than others. A 2005 survey of nearly 10 000 South Africans over the age of 30 found that high blood pressure had the highest prevalence in the black community, with 59% of black African people, 55% of Indian and coloured people and 50% of white people diagnosed with the condition.
This reflects figures from the United States from 1999-2004, which show that adult blacks in the United States have the highest age-adjusted rates of high blood pressure prevalence at 39.1%, compared to 28.5% in whites and 27.8% in Mexicans. Adult blacks are also prone to developing the condition at a younger age, to suffer from more elevated blood pressure levels if they do develop it, and to experience more damage and cardiovascular events as a result.
Lower tolerance to salt
“High blood pressure is a serious issue for South Africans,” confirms Dr Mike Ramaboea from the Louis Pasteur Hospital in Pretoria. “Sadly, we don’t have enough recent data and studies on prevalence, but my own experience mirrors the results of the American study. I see a lot of adult black patients with the condition. The average age is about 32 years old, but some are as young as 21 or 22.”
While there are several potential causes of high blood pressure, most experts agree that diet is one of the chief culprits. Numerous studies have linked excessive salt consumption to high blood pressure, for example, and some commentators believe this is likely to be a significant contributing factor here in South Africa. “Based on my own personal experience, I would argue that black people appear to have a lower tolerance for salt,” agrees Dr Ramaboea.
The link between salt and high blood pressure
Our bodies need salt. Among other tasks, the kidneys use the mineral to control the amount of water in the body and to ensure our blood’s normal pH is maintained. The kidneys also regulate the amount of salt in our bodies by excreting the excess in our urine. If our salt intake is too high, however, the kidneys cannot keep up and the excess builds up in our bloodstream.
Salt retains or attracts water and so, the more of it there is in our blood, the more water is retained as well. This increases the volume of fluid being pumped around the body and, as a result, more pressure is needed to push it. That is why doctors recommend reducing the amount of salt you consume each day as an important part of high blood pressure treatment and prevention.
You only need 69 mg of sodium per day (1g of salt contains 0.4g sodium). Even though a teaspoon of salt contains considerably more - about 2 300 mg - dieticians say that it is an okay amount for people with normal blood pressure to consume daily. If you have or are at risk of high blood pressure, you should limit the sodium in your diet to 1 500 mg per day.
The hidden salt in our diets
Most of the salt we consume doesn’t come from what we shake onto our meals, but what is already ‘hidden’ in our food. The food industry uses salt to make food taste better and last longer. As a rule, the more processed the food, the more salt it is likely to have in it. "Take aways", ready meals and canned foods, for example, all tend to have extremely high levels of salt in them. As do sweets, breads, cereals, red meats, sugar, milk and shellfish. Foods with low levels of salt tend to be unrefined, fresh foods, such as fruits, vegetables, beans, rice, lentils and pasta.
Read the labels on the food you buy. You might be surprised at how many products contain high levels of salt. If the label says anything more than 1.25g salt (or 0.5g sodium) per 100g/ml, then it should be considered high. Also, try not to cook with salt or add it to your meal at the table, use an alternative seasoning instead.
Get tested regularly
While the good news is that high blood pressure can usually be managed by making these kinds of dietary and lifestyle changes - and taking medicines, if necessary - the condition’s lack of symptoms means that people are often not aware that they have it until it is too late and major complications have arisen. So the best approach is to have your blood pressure checked regularly by a medical professional. “Every adult South African should get tested regularly,” maintains Dr Ramaboea, “especially black patients over the age of 30, should have their blood pressure checked at least once a year.”
Bespoke Strategic Communications press release
(Health24, July 2011)
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