CAH Diet and Food Restrictions: What Should You Eat?

There is no single “CAH diet” that cures the condition or replaces the need for medication. However, what you eat supports your overall health and medical treatment. Nutritional needs depend entirely on your specific CAH subtype and treatment plan. For example, people with the salt-wasting form of CAH may need to manage their salt intake carefully, while everyone taking long-term steroid medications should focus on supporting bone health and metabolism.

⚠️ Crucial Safety Warning: Sick Days and Emergencies

Extra salt or fluids are never a substitute for medication. If you experience vomiting or diarrhea, your body may not absorb your oral glucocorticoid (steroid) medications, which can quickly lead to a life-threatening adrenal crisis ^[1].

• Do not rely on food or salt during illness.
• Follow your doctor’s individualized “sick-day” or stress-dose plan to increase your steroid dose when ill ^[2].
• Seek urgent medical care and use emergency injectable hydrocortisone (if prescribed) if you have severe weakness, dizziness, confusion, repeated vomiting, or an inability to keep medication down.
• Never stop or change your steroid or fludrocortisone dose without medical supervision.

Managing Salt and Fluids by CAH Subtype

In salt-wasting classic CAH, the body lacks aldosterone, a hormone that retains sodium (salt). This leads to salt loss in the urine. People with simple-virilizing classic CAH or nonclassic CAH typically make enough aldosterone and do not need extra salt; in fact, extra salt could raise their blood pressure.

• Infants: Babies with salt-wasting CAH may be prescribed specific sodium chloride supplements because breast milk and formula do not contain enough sodium ^[3][4]. Caregivers should never add household salt to an infant’s bottle or food unless given precise, prescribed instructions from a doctor.
• Older Children and Adults (Salt-Wasting): If you have the salt-wasting subtype, your doctor might encourage you to consume salty foods or extra fluids during hot weather or intense exercise when you sweat out salt ^[1][2].
• Balancing Medication: To help the body hold onto salt, doctors often prescribe a mineralocorticoid medication called fludrocortisone. Taking too much fludrocortisone or eating unlimited salt can cause hypertension (high blood pressure) ^[5]. Your endocrinologist will routinely check your blood pressure, electrolytes (blood minerals like sodium and potassium), and a blood test called renin to ensure your salt and fludrocortisone levels are properly balanced ^[6].

Bone Health, Calcium, and Vitamin D

People with classic CAH take glucocorticoids (such as hydrocortisone) to replace the cortisol their bodies cannot make. When taken at physiologic replacement doses (the amount a body would naturally make), steroids usually do not harm bones. However, prolonged exposure to higher doses can lower bone mineral density (BMD), which is a measure of bone strength ^[7].

Studies show that some individuals with CAH have low calcium or vitamin D levels ^[8]. Having adequate vitamin D is associated with better bone density in people with CAH ^[9].

• Dietary Sources: Focus on calcium-rich foods like dairy or fortified plant milks, and vitamin D sources like fortified foods or fatty fish.
• Supplements and Scans: Ask your doctor if you need blood tests to check your vitamin D levels before starting supplements. Depending on your steroid exposure and risks, they may also recommend a DEXA scan (a specialized X-ray to measure bone thickness) ^[7]. Never stop or reduce your steroid medications out of concern for your bones without talking to your doctor.

Metabolism and Healthy Growth

While glucocorticoids are essential, taking supraphysiologic doses (amounts higher than the body naturally produces) can alter metabolism. Higher doses are associated with an increased risk of weight gain, higher BMI (Body Mass Index), and insulin resistance (when cells don’t respond well to insulin, raising blood sugar) ^[10][11]. People with CAH may also face elevated cardiovascular risks over time ^[12].

• Focus on Balanced Nutrition: Rather than restricting calories—which can be harmful, especially for growing children—focus on a balanced diet of lean proteins, vegetables, and whole grains.
• Monitor Trajectories: Your medical team will monitor growth charts, weight trends, blood pressure, and sometimes glucose (blood sugar) and lipids (cholesterol) to adjust your treatments safely ^[12].
• Seek Expert Advice: Consider working with a registered dietitian who understands endocrine disorders, and never adjust your CAH medications to try and manage your weight.