One of the most studied diets happens to be a diet that kidney patients can benefit from. The DASH Diet is a foundational diet used by many dietitians and practitioners to support heart (and kidney) health. Our registered dietitian covers what a DASH diet is, how a DASH Diet can help chronic kidney disease patients, and considerations for kidney patients when starting a DASH Diet.
Table of Contents
What is the DASH Diet?
The DASH Diet stands for Dietary Approaches to Stop Hypertension. It was created in the 1990s by the National Institute of Health (NIH).
The NIH performed research to evaluate the effectiveness of different dietary interventions that could treat hypertension. The DASH Study looked at how diet can impact blood pressure.
They found that a diet with fruits, vegetables, low-fat dairy and a diet low in saturated and overall fat significantly reduced blood pressure. (1)
Now, major groups including the American Heart Association and National Heart, Lung, and Blood Institute use the DASH Diet guidelines to encourage healthier eating to reduce high blood pressure levels.
A Low-Sodium Diet
The DASH Diet is one of the best ways to implement a low-sodium diet. The DASH trial looked at normal sodium intake against upper limits of recommendations and low sodium intake.
They found those that followed the food groups of the DASH diet and limited sodium to 1,200 milligrams per day had the best reduction in blood pressure. (2)
Read more about a low sodium diet.
Food Groups of the DASH Diet
There are several nutritional components for a DASH diet. Here are those different parts of a DASH Diet.
Whole Grains
The DASH Diet includes 6 to 8 servings of whole grains. A serving can look like:
- 1 regular slice of bread
- 1 cup ready-to-eat cereal
- ½ cup of cooked grains, pasta, or cereal
- 3 cups popped popcorn
Fruits & Vegetables
Fruits and Vegetables are an important part of a DASH Diet. The diet includes 4 to 5 servings of fruits and 4 – 5 servings of vegetables per day.
An example of a serving of fruit or vegetable can look like:
- 1 cup leafy greens (such as spinach or cabbage)
- ½ cup raw fruits or vegetables (such as blackberries or asparagus)
- ½ cup cooked fruits or vegetables (such as steamed carrots or sautéed apples)
- 4 ounces fruit or vegetable juice
Meat, Poultry, and Fish
The DASH Diet includes 6 or less daily servings of meat, poultry, and/or fish.
A serving is one ounce of cooked meat or poultry, or 1 large egg.
Low-Fat Dairy
The DASH Diet includes 2-3 servings of low-fat dairy each day.
A serving can be one cup of milk or yogurt, or 1 ½ ounces of cheese.
Nuts, Seeds, and Legumes
The DASH Diet recommends 4 – 5 servings per week of these foods.
Examples of servings include:
- ⅓ cup nuts
- 2 tablespoons (Tbsp) nut butter
- 2 Tbsp seeds
- ½ cup cooked beans or peas
Fats and Oils
Many may be surprised that the DASH Diet includes fats and oils as part of their recommended diet.
Fats and oils provide satiety when we eat. They also provide healthy fats like omega-3s.
The DASH Diet recommends 2 to 3 servings of fats and oils per day. Additionally, less than 10% of calories should come from saturated fats.
Examples of servings include:
- 1 teaspoon (tsp) margarine or plant-based margarine
- 1 tsp oil (avocado, olive, canola, or flaxseed for example)
- 1 Tbsp mayonnaise
- 2 Tbsp salad dressing
- 1/3 avocado (50 grams)
Sweets and Added Sugars
This is something more limited in the DASH Diet. However, it’s still accounted for – after all, we can enjoy desserts from time to time.
The DASH Diet advises that less than 10% of calories come from added sugars.
Examples of added sugars include:
- 1 Tbsp sugar, jelly or jam
- ½ cup sorbet
- 1 cup lemonade (made with sugar)
It’s important to note that fruits, whether fresh, frozen or canned, are not included as added sugars.
DASH Diet Chart
Below is a chart for easy reference of what the DASH Diet includes.
Food Group | Servings Per Day or Per Week |
---|---|
Whole grains | 6 – 8 per day |
Fruit | 4 -5 per day |
Vegetables | 4 – 5 per day |
Low-fat or non-fat dairy | 2 – 3 per day |
Lean meats, poultry or fish | Six ounces or less per day |
Nuts, seeds, beans and peas | 4 – 5 servings per week |
Fats and oils | 2 to 3 servings per day |
Sweets and added sugars | 5 servings or fewer per week |
DASH Diet Benefits
There are many different ways a person may benefit when following the DASH Diet. In this section, we’ll touch on the research related to different nutritional concerns.
Better Blood Pressure
As mentioned, this diet was targeted at addressing high blood pressure. Therefore, those with high blood pressure will likely benefit from a DASH Diet.
Participants both with and without high blood pressure experienced better blood pressure levels. Significant reductions in both systolic and diastolic blood pressure were observed.
Age may be a factor in the improved blood pressure and lower sodium intake. Participants under the age of 50 had blood pressure reduction with higher sodium intake.(3)
Note that this study did not look at patients with chronic kidney disease.
Weight Management
For those with a desire to lose weight, a DASH Diet may be a way to lose weight when appropriate.
A low-calorie DASH Diet has shown to help higher-weight individuals lose weight more safely and effectively compared to other low calorie diets.(4)
Lower Cholesterol, LDL and Triglycerides
The DASH Diet has been shown to reduce total cholesterol and LDL cholesterol.(5)
LDL stands for low-density lipoprotein and is considered the “bad cholesterol.”
DASH has also been shown to reduce triglyceride levels.(6) Excessive triglycerides can increase the risk of heart disease and stroke.
Glucose Control for Diabetes
The DASH Diet has also shown to reduce the risk of developing type 2 diabetes. The diet increased insulin sensitivity.(7)
Type 2 diabetes often requires insulin dosing to compensate for decreased insulin sensitivity. A DASH diet has been shown to reduce daily insulin usage for patients with type 2 diabetes.(8)
In fact, the DASH diet has been shown to decrease future type 2 diabetes by 20%.(9)
Better Blood Sugars for Type 1 Diabetes
Type 1 diabetes is more commonly occuring in younger people. This is because this type of diabetes means there is no insulin production in the body.
A DASH diet has been shown to decrease the frequency of high blood sugars.(10)
DASH Diet and Kidney Disease
The DASH Diet can be a great option for patients with chronic kidney disease. It makes sense that a diet promoting lower blood pressure would help, given that high blood pressure is one of the top causes of chronic kidney disease.
However, you may be thinking, “how can I follow a DASH Diet if I have kidney disease?” Don’t worry – as a renal dietitian I can show you how to align both the DASH Diet and the renal diet.
Here are some considerations for a kidney patient looking to start the DASH diet.
Potassium
Potassium comes to mind with kidney disease patients frequently, as it has historically been demonized in the renal diet.
However, it’s important to remember that not all kidney disease patients are required to limit their potassium. Some kidney disease patients need to eat higher amounts of potassium.
Patients on dialysis may be restricted to 2,000 to 3,000 milligrams of potassium per day. Certain dialysis patients, like those using peritoneal dialysis, may consume upwards of 4,000 milligrams per day. (11)
Kidney patients with higher kidney function (GFR >/= 60) are even shown to benefit from higher potassium intake. Therefore, it’s often recommended these kidney patients aim for 4,700 milligrams per day. (12)
Only your healthcare provider can tell you if you need to limit potassium.
Additionally, it’s still possible to follow the DASH Diet even with a potassium restriction.
Low Potassium Fruits and Vegetables
If a low potassium diet is part of your diet plan, a DASH diet can still be followed.
Aim for the recommended 8-10 servings of fruits and vegetables daily by focusing on the lower potassium options.
While there is no true definition of a low potassium food, most professionals go by a 200 milligram amount per serving.
Examples of low potassium fruits and vegetables include:
- Bell peppers (178 mg per cup)
- Cucumbers (168 mg per cup)
- Cabbage (172 mg per cup)
- Blueberries (130 mg per cup)
- Eggplant, steamed (119 mg per ½ cup)
- Onions (sliced, raw, 168 mg per cup)
- Watermelon (diced, 170 mg per cup)
- Jicama (196 mg per cup)
- Radicchio (120 mg per cup)
If a person was to eat each of these in a day, it would total to 9 servings of fruits and vegetables and a total of only 936 milligrams of potassium.
This would still leave plenty room in the diet to account for other sources of potassium such as grains, nuts, seeds, and even animal meat.
You can find many more examples of low potassium fruits and vegetables in our Low Potassium Diet article.
Protein
As mentioned above, the DASH Diet includes 6 ounces or less of lean protein per day. This may be a conflict for some chronic kidney disease patients that need to follow a Low Protein Diet or use ketoanalogues.
A 100-gram serving (3.5 ounces) of chicken breast provides 31 grams of protein.(13) So, six ounces of chicken breast would total to 53 grams of protein.
A 100-gram (3.5 ounce) serving of salmon provides 20 grams of protein.(14) Six ounces of salmon would total to 34 grams of protein.
One large egg provides 6 grams protein, 66 milligrams potassium and 93 milligrams phosphorus.(15)
However, this recommendation is still significantly lower than what people usually eat. Dietary surveys have shown that women eat about 59 – 70 grams of protein per day and men 74 – 100 grams per day.(16) The lower ranges are generally the older population, over 70.
Therefore, even a DASH Diet protein guide of 6 ounces per day may actually be less protein than a person would normally eat.
Plant Proteins
Substituting animal proteins for plant proteins may further benefit kidney patients.
A study published in 2022 found that participants that used plant proteins for their protein sources improved their fasting blood glucose and systolic blood pressure.(17)
Examples of plant proteins include:
- Tofu
- Tempeh
- Edamame
- Lentils
- Quinoa
- Peanuts
Dairy
Some kidney patients may choose to avoid dairy. This is often due to the potassium and phosphorus content of dairy foods. It may also be for ethical reasons.
However, including dairy can be beneficial. For example, those that get calcium oxalate kidney stones benefit from including dairy with meals. The dairy binds to oxalates in foods, reducing the risk of kidney stones. (18)
Additionally, blood pressure is better controlled when people eat enough potassium, magnesium, and calcium. (19, 20, 21)
Phosphorus
Kidney patients are often advised to limit phosphorus in their diet. However, the source of phosphorus can make a big difference.
Organic phosphorus (aka the naturally occurring phosphorus) from dairy is absorbed by about 60%. (22)
If potassium and phosphorus are a concern, choosing a soy-based yogurt can still provide benefits as it includes lower potassium and phosphorus, but higher magnesium. (23)
Calcium
Some kidney patients may require more calcium, while some may need to limit it to prevent high levels of calcium.
In general, aiming for approximately 1,000 milligrams of calcium per day is recommended for calcium balance with kidney disease patients. (24)
Including low-fat dairy or calcium-fortified products may be helpful for kidney patients to reach this calcium goal.
Additionally, calcium can be found in other food sources, such as leafy green vegetables.
It’s important to note that vitamin D also plays a role in how much calcium our body absorbs. Some may benefit from a supplement. However, too much vitamin D can also result in high calcium levels.
Be sure to discuss supplements with your provider before starting, to ensure it’s the right dose and plan for you.
Summary
The DASH Diet is one of the most researched diets. It has been proven to reduce blood pressure for those with high blood pressure.
Key food groups of the DASH Diet include whole grains, dairy, fruits, and vegetables. It also includes smaller amounts of lean meats, nuts, seeds, legumes. Healthy fats and added sugars are also included but in moderation.
Kidney patients often struggle with high blood pressure, whether it was the cause or a result of chronic kidney disease.
Nutrients like potassium, protein, phosphorus and calcium may be a concern for kidney patients. However, modifications like focusing on low-potassium fruits and vegetables, and using organic phosphorus sources can be applied for a DASH diet for kidney disease.
Ask your healthcare provider what steps you can take to follow a DASH diet. Working with a dietitian is a great way to get personalized advice and guidance while supporting your kidney health goals.
Jen Hernandez is a registered dietitian and board-certified specialist in renal nutrition. She has nearly a decade of experience with kidney disease patients in all stages - from stage 1 through kidney transplant. Jen writes on the blog of Plant-Powered Kidneys to help reach and teach more kidney patients about how they can enjoy more foods in a plant-based diet while protecting kidney health.