Reducing hypertension with the DASH diet

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1. Where does the DASH diet come from and how was it designed?

The DASH diet is the product of an in-depth study carried out in the 1990s by three, prestigious American universities (Harvard, John Hopkins and Duke) on behalf of the Pennington Biomedical Research Centre and the National Health Institute. The DASH diet is centred around lean meats, grains, fruit and all vegetables, green or otherwise.

2. Has the DASH diet’s effectiveness really been demonstrated?

In one of many studies, American scientists tested this DASH diet on 459 individuals with high blood pressure, who were divided into three groups: the first had to follow an unhealthy diet; the second had to eat more vegetables but had to avoid fatty foods and the last group followed the DASH diet. For the third group, maximum blood pressure was reduced by an average of 1.14 points and minimum blood pressure was reduced on average by 0.5 points. The DASH diet is now recognised by medical professionals and nutritionists the world over.

3. Is the DASH diet only beneficial for people with high blood pressure?

No, DASH is suitable for lots of different people. This type of diet, rich in fruit and vegetables, can even reduce the risks of developing certain cancers. Since the DASH diet incorporates dairy products, crammed full of calcium, it can also contribute to the reduction of risks of osteoporosis (a conclusion made by Duke University in the United States, and Cambridge University in the UK). Finally, because the DASH diet is low in saturated fats and cholesterol, it prevents certain problems connected with the heart from occurring.

4. What role do vegetables play in this DASH diet, designed to fight hypertension?

First of all, vegetables are not very calorific, and we know there is a link between being overweight and hypertension. Furthermore, vegetables have considerable anti-oxidising properties, which help blood vessels stay in good working order. On top of this, when a group of vegetarians was studied, it was noticed that the rate of individuals suffering from high blood pressure was much lower.

5. Why does DASH recommend that sugary and fatty foods be kept to a minimum?

Yet again, the number one objective for an individual suffering from, or at risk of hypertension is to control weight better, and sugary and fatty foods are very calorific. But this is not the only benefit: the DASH strategy can improve the balance of lipidic molecules (fat molecules) in the blood. Another objective is to reduce the level of “bad cholesterol” or LDL.

6. Why does the DASH diet put emphasis on milk and dairy products?

This is because dairy foods are full of calcium, one of the minerals needed for dilation and contraction of blood vessels. But let’s be clear on one thing; the DASH diet prescribes “light” dairy products, which means they are based on skimmed milk. Different studies have shown that the calcium consumed during a meal only slightly reduces blood pressure. The secret lies in combining foods which are eaten with dairy products.

7. Is cheese recommended in a diet favourable for reducing hypertension?

In principle, the response should be a resounding “no”! Cheese is not a good source of polyunsaturated fatty acids in the Omega group (like fish for example). It is these that reduce the level of cholesterol or triglycerides in the blood. On the contrary, “yellow” cheeses are crammed full of saturated fat and salt. There are, however, a few exceptions when it comes to light cheeses (ricotta is just one example).

The below figures speak for itself when you know the dangers of salt (sodium) in cases of hypertension:

• Parmesan - 1,862 (mg/100g)

• Gorgonzola - 1,395 (mg/100g)

• Provolone - 876 (mg/100g)

• Camembert - 842 (mg/100g)

• Cheddar - 620 (mg/100g)

• Cottae - 406 (mg/100g)

• Mozzarella - 373 (mg/100g)

• Fresh ricotta - 84 (mg/100g)

To remind you, the daily recommended intake of sodium is 1,600mg a day, with an intake well under this amount recommonded by doctors if dealing with hypertension.

8. According to the DASH diet, what would be an ideal menu?

Here is an example:

• GRAIN: Brown rice, oats, whole grains: Around four cups a day.

• FRUITS: Strawberries, apples, raisons, tangerines, bananas and watermelons. You should aim to eat four portions of fruit a day..

• VEGETABLES: Spinach, carrots and broccoli should be present in menus all the time. The DASH diet suggests four to five portions per day (1 cup) in both raw and cooked forms in equal quantities.

• DAIRY PRODUCTS: The equivalent of a cup of yoghurt or skimmed milk, or even better, a slice of light cheese two or three times a day.

• MEATS: Poultry, lean beef or fish fillet. You should not consume more than two small portions a day of this food group.

• OLEAGINOUS NUTS AND FRUIT: Nuts, chestnuts, beans, peas. 1/2 a cup of oleaginous fruit and 1/2 cup of pulses, four times a week.

• OILS: Light margarine and maize oil are the most recommended. But you should not consume more than three teaspoons a day.

• DESSERTS AND CAKES: Gelatinous cakes, jellies and also sorbets (low calorie options obviously), are the only acceptable desserts in this diet. But the portion should not exceed one desert spoon, five times a week.

Laurent Juillet

More information:
Sodium
Hypertension
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