Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!

Diets can be designed to restrict (or eliminate) virtually any nutrient or food component. The most commonly used restricted diets are those that limit sodium, fat, carbohydrate, and protein. Other restrictive diets include gluten restriction in gluten enteropathy, potassium and phosphate reduction in CKD, and elimination of certain allergens for food allergies.

SODIUM-RESTRICTED DIETS

Low-sodium diets can be useful in the management of hypertension and in conditions in which sodium retention and edema are prominent features, particularly heart failure, chronic liver disease, and CKD. Sodium restriction may be beneficial with or without diuretic therapy. When used in conjunction with diuretics, sodium restriction may allow lower dosages of diuretic medications and may prevent side effects. For example, sodium restriction decreases diuretic-related potassium losses by reducing distal tubule sodium delivery.

Typical American diets contain 4–6 g (175–260 mEq) of sodium per day. A no-added-salt diet contains approximately 3 g (132 mEq) of sodium per day. Further restriction can be achieved with diets of 2 or 1 g of sodium per day. Diets with more severe restriction are difficult to adhere to and are rarely used. National Academies of Sciences, Engineering, and Medicine guidelines recommend 2.3 g of sodium per day (approximately 1 teaspoon of salt).

Dietary sodium includes sodium naturally occurring in foods, sodium added during food processing, and sodium added during cooking and at the table. Approximately 80% of dietary intake in American diets is from processed and pre-prepared foods. Diets designed for 2.3 g of sodium per day require elimination of most processed foods, added salt, and foods with high sodium content. Many patients with mild hypertension will achieve significant reductions in blood pressure (approximately 5 mm Hg diastolic) with this degree of sodium restriction.

Diets allowing 1 g of sodium require further restriction of commonly consumed foods. Special “low-sodium” products are available to facilitate such diets. These diets are difficult for most people to follow and are generally reserved for hospitalized patients, most commonly those with heart failure, CKD, or severe liver disease and ascites.

FAT-RESTRICTED DIETS & LOW–SATURATED FAT DIETS

Traditional fat-restricted diets are useful in the treatment of fat malabsorption syndromes. Such diets will improve the symptoms of diarrhea with steatorrhea independent of the primary physiologic abnormality by limiting the quantity of fatty acids that reach the colon. The degree of fat restriction necessary to control symptoms must be individualized. Patients with severe malabsorption can be limited to 40–60 g of fat per day. Diets containing 60–80 g of fat per day can be designed for patients with less severe abnormalities.

Fat-restricted diets that specifically restrict saturated fats are the mainstay of dietary treatment of hyperlipidemia with elevated LDL cholesterol (see Chapter 28). Similar diets are often recommended for the prevention of CAD (see Chapter 10). The large Women’s Health Initiative Dietary Modification Trial, however, did ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.