The DASH diet, step by step

How DASH works

DASH stands for Dietary Approaches to Stop Hypertension. It came out of US research funded by the National Heart, Lung, and Blood Institute (NHLBI) in the 1990s. Researchers fed people a diet rich in fruit, vegetables and low-fat dairy and watched their blood pressure drop. Later trials showed that cutting sodium on top of that lowered it further.

You eat more foods that bring potassium, magnesium, calcium and fibre, and less of the salt that pushes blood pressure up. It's not a cleanse or a branded plan. It's a way of eating you keep.

What to eat more and less of

More: leafy greens, tomatoes, carrots, sweet potatoes, bananas, oranges, berries, oats, brown rice, wholemeal bread, beans and lentils, unsalted nuts, skimmed or semi-skimmed milk, plain yogurt, fish and skinless chicken.

Less: salty packaged food, ham, bacon and sausages, fatty cuts of red meat, full-fat cheese, fizzy drinks, cakes and biscuits.

Salt is the big one, and most of it isn't from your salt shaker. It's already in bread, cheese, cured meat, soup, sauces, ready meals and takeaways. One teaspoon of salt holds about 2,300 mg of sodium, your whole day's limit. On UK labels you'll see salt rather than sodium: multiply sodium by 2.5 to get salt, so 2,300 mg of sodium is about 5.75 g of salt.

A sample day

This roughly hits the 2,000 kcal targets in the table further down.

• Breakfast: a cup of cooked oats made with semi-skimmed milk, topped with a sliced banana and a spoon of unsalted chopped walnuts. A slice of wholemeal toast and a small glass of orange juice.
• Lunch: wholemeal wrap with sliced chicken breast you cooked yourself (not deli meat), lettuce, tomato and a smear of hummus. An apple and a pot of plain yogurt.
• Snack: carrot sticks and a small handful of unsalted almonds.
• Dinner: baked salmon with a big pile of steamed broccoli and green beans, a cup of brown rice, and a side salad dressed with oil and vinegar.
• Dessert: a bowl of berries, fresh or thawed frozen.

That's roughly 7 grain servings, 5 of vegetables, 5 of fruit, 2 to 3 of dairy and about 6 oz of chicken and fish. The nuts count toward your weekly target.

Why people like it

• You buy everything at a normal supermarket. No powders, bars or apps required.
• The whole family can eat the same meals.
• It works for vegetarians. Swap meat and fish for beans, tofu, eggs and dairy.
• It lowers LDL cholesterol too, not just blood pressure.

Common mistakes

• Doubling your fibre overnight. Going from two to ten portions of fruit and veg in a day can leave you bloated and gassy. Add a serving or two a week and drink more water.
• Only hiding the salt shaker. It helps, but most sodium comes from packaged and restaurant food. Two slices of bread, a bowl of canned soup and a takeaway pizza can blow past 2,300 mg on their own.
• Skipping the potassium foods. Cutting salt is half the plan. The fruit, vegetables, beans and dairy do the other half.
• Trusting "low-fat" labels. Low-fat biscuits can be loaded with added sugar.
• Quitting in week one. Food tastes bland when you first cut salt. Your taste buds adjust over a few weeks, so give it time.

How to start this week

1. Check the labels on the five packaged foods you eat most, often bread, cereal, cheese, sauces and soup. Swap the saltiest one for a lower-salt version.
2. Add one fruit and one vegetable serving to your day.
3. Switch one refined grain for a whole grain, like brown rice for white.
4. Make snacks unsalted: nuts, fruit, yogurt or raw veg.
5. Flavour food with lemon, garlic, herbs, pepper and vinegar instead of salt.

Easy swaps:

• Salted crisps → unsalted popcorn or nuts
• Ham sandwich → leftover roast chicken or egg sandwich
• Canned soup → homemade soup, or a "no added salt" version
• Stock cube → low-salt stock, or herbs and a splash of wine or lemon

Shopping list and cost tips

A basic week's list: oats, wholemeal bread, brown rice, frozen mixed vegetables, a bag of carrots, spinach, bananas, apples, frozen berries, tinned tomatoes and beans labelled "no added salt", dried lentils, unsalted peanuts, semi-skimmed milk, plain yogurt, eggs, chicken thighs and tinned salmon.

• Frozen and tinned produce counts. Rinsing tinned beans in a sieve washes off some of the salt.
• Buy big tubs of plain yogurt and add your own fruit.
• Bananas, carrots, cabbage and potatoes are low-cost sources of potassium.

Check with your doctor first if...

DASH is safe for most adults, but a few situations change the rules:

• You have kidney disease. DASH is high in potassium and phosphorus, which damaged kidneys may not clear well.
• You take blood pressure medicine such as ACE inhibitors, ARBs or potassium-sparing diuretics, which can raise potassium levels.
• You're thinking of using a salt substitute. Many are made of potassium chloride, which is a problem with the conditions above.
• Your blood pressure is already low, or you get dizzy when you stand up.

More on potassium and sodium balance is in our electrolytes entry.

Daily servings by food group

These are the NHLBI targets for about 2,000 kcal a day. If you need fewer calories, aim for the lower end. If you need more, go higher.

Is it right for you?

Questions people ask

Sources

• NHLBI: DASH Eating Plan
• NHLBI: Following DASH
• MedlinePlus: Understanding the DASH Diet
• Mayo Clinic: DASH Diet