DASH stands for Dietary Approaches to Stop Hypertension. It was developed in the 1990s by the US National Institutes of Health specifically to combat high blood pressure without medication. What researchers discovered was a dietary pattern that does far more than just lower blood pressure - it protects against heart disease, stroke, diabetes, and kidney disease.
Unlike many "diets" that come and go, DASH has been consistently ranked among the healthiest eating patterns by cardiologists, nutritionists, and major health organisations. The British Heart Foundation, American Heart Association, and NHS all recommend it for cardiovascular health.
How DASH Works
The DASH diet doesn't rely on any single "magic" food or nutrient. Instead, it's the combination of several factors working together:
The Science Behind the Results
High potassium - Fruits, vegetables, and dairy provide potassium, which helps blood vessels relax and counteracts the effects of sodium.
Adequate calcium & magnesium - These minerals support healthy blood pressure regulation and heart rhythm.
Low sodium - Reducing salt intake to 1,500-2,300mg daily reduces fluid retention and vessel wall stress.
High fibre - Whole grains and vegetables improve cholesterol profiles and blood sugar control.
Limited saturated fat - Choosing lean proteins and healthy fats protects artery health.
What to Eat on DASH
DASH isn't about restriction - it's about emphasis. Here's what a typical day looks like on a 2,000-calorie DASH plan:
Whole Grains: 6-8 servings
Brown rice, wholemeal bread, oats, quinoa. One serving = 1 slice bread or 1/2 cup cooked grains
Vegetables: 4-5 servings
All colours, especially leafy greens. One serving = 1 cup raw or 1/2 cup cooked
Fruits: 4-5 servings
Whole fruits over juices. One serving = 1 medium fruit or 1/2 cup chopped
Low-fat Dairy: 2-3 servings
Milk, yoghurt, cheese. One serving = 1 cup milk or yoghurt, 40g cheese
Lean Protein: 6 or fewer servings
Fish, poultry, lean meat. One serving = 30g cooked meat or fish
Nuts & Seeds: 4-5 per week
Almonds, walnuts, sunflower seeds. One serving = 30g nuts
DASH Priorities
- Leafy greens (spinach, kale)
- Berries and citrus fruits
- Beans and lentils
- Oily fish (salmon, mackerel)
- Low-fat dairy products
- Whole grains (oats, brown rice)
- Nuts and seeds
- Olive oil
DASH Limits
- Salt (under 2,300mg, ideally 1,500mg)
- Red meat (limit to 1-2 times weekly)
- Added sugars and sweets
- Sugary drinks
- Full-fat dairy products
- Processed meats (bacon, sausages)
- Fried foods
- Alcohol (if consumed, moderate only)
The Evidence: What the Research Shows
DASH is one of the most studied dietary patterns. The original DASH trial (1997) and the follow-up DASH-Sodium trial (2001) established its effectiveness, and subsequent research has only strengthened the case:
- Blood pressure - Reduces systolic BP by 8-14 mmHg in people with hypertension, comparable to a single blood pressure medication
- Cardiovascular disease - Following DASH is associated with 20% lower risk of heart disease and 29% lower risk of heart failure
- Stroke - Those following DASH have 19% lower stroke risk
- Type 2 diabetes - DASH reduces diabetes risk by up to 20%
- Kidney disease - Slows progression of chronic kidney disease in those with existing kidney problems
- Cognitive function - MIND diet (DASH + Mediterranean hybrid) shows promise for reducing dementia risk
If You're on Blood Pressure Medication
DASH can be powerful enough to reduce or eliminate the need for blood pressure medication in some people. However, never adjust or stop medication without discussing with your doctor. The combination of DASH and medication can sometimes lower blood pressure too much. Work with your GP to monitor and adjust safely.
DASH vs Mediterranean Diet
These two evidence-based eating patterns share many similarities - both emphasise vegetables, fruits, whole grains, and healthy fats. The main differences:
- Dairy - DASH emphasises low-fat dairy (2-3 servings daily) for calcium and potassium; Mediterranean is more neutral on dairy
- Fat - DASH is lower in total fat; Mediterranean embraces olive oil and fatty fish more liberally
- Alcohol - Mediterranean traditionally includes moderate red wine; DASH is more cautious about alcohol's effects on blood pressure
- Sodium - DASH has specific sodium targets (1,500-2,300mg); Mediterranean doesn't explicitly limit salt
Both are excellent choices. DASH may be preferable if blood pressure is your primary concern; Mediterranean if you want a slightly more flexible approach to fats and oils.
Practical Tips for Starting DASH
Don't try to change everything at once. Research shows gradual changes stick better than dramatic overhauls:
- Week 1-2: Add one extra serving of vegetables to your main meal and one extra piece of fruit daily
- Week 3-4: Switch from white bread/rice to wholemeal/brown alternatives
- Week 5-6: Start reading sodium labels; choose lower-sodium options where possible
- Week 7-8: Replace some red meat meals with fish, chicken, or bean-based dishes
- Ongoing: Gradually reduce salt in cooking; your taste buds adapt within 2-3 weeks
Watch Out for Hidden Sodium
Most dietary sodium doesn't come from the salt shaker - it's in processed foods. The biggest culprits:
- Bread and rolls (sodium adds up over multiple servings)
- Processed meats (bacon, ham, sausages)
- Pizza and ready meals
- Tinned soups and sauces
- Cheese (especially hard and processed varieties)
- Restaurant and takeaway food
Key Takeaway
DASH isn't a quick fix or a fad - it's a sustainable way of eating backed by decades of research. You don't need to follow it perfectly to see benefits. Even partial adoption improves cardiovascular health. Start with one or two changes and build from there.
References
- Appel, L.J. et al. (1997). A clinical trial of the effects of dietary patterns on blood pressure. New England Journal of Medicine
- Sacks, F.M. et al. (2001). Effects on blood pressure of reduced dietary sodium and the DASH diet. New England Journal of Medicine
- Chiavaroli, L. et al. (2019). DASH Dietary Pattern and Cardiometabolic Outcomes. American Journal of Clinical Nutrition
- Siervo, M. et al. (2015). Effects of the DASH diet on cardiovascular risk factors. British Journal of Nutrition
- British Heart Foundation. (2024). Healthy eating for your heart.
