Many vitamins and minerals are water-soluble and can be significantly reduced during cooking. A boiled or stewed chicken does indeed lose more of its B vitamins than a roasted bird, and the same holds true for minerals such as selenium, phosphorus and potassium.
Boiling, Pressure Cooking, and Microwaving Meats
Boiling meats for at least 10 minutes has been shown to reduce potassium content by about half.
Most meats add some potassium to your meals. Chicken breast has the most per 3-ounce serving with 332 milligrams, but beef and turkey breast contain 315 and 212 milligrams, respectively.
If boiled at least 10 minutes in a large pot of water, potassium is reduced by at least half the original amount.
Cooking in water, pressure cooking and cooking in a microwave oven reduced potassium levels in all food groups, particularly in cereals and derivatives, fruits and derivatives, meats and derivatives, legumes, and leafy and cruciferous vegetables.
Water pills (diuretics) help rid your body of extra potassium. They work by making your kidney create more urine. Potassium is normally removed through urine. Potassium binders often come in the form of a powder.
One chicken thigh or drumstick has 130 to 165 milligrams of potassium. One-half chicken breast has 220 milligrams and 3 ounces of turkey range from 244 to 256 milligrams. These choices are a little high for a low potassium diet, but could be part of a meal if other food choices have very low potassium.
Red meat. Some types of protein may be harder for the kidneys, or the body in general, to process. These include red meat.
Foods to limit or avoid
Limit high-potassium foods such as: bananas. avocados. raisins.
All vegetables should be boiled, rather than steamed or microwaved. Boiling allows some of the potassium to leach into the water.
Meat and fish contain a moderate amount of potassium. However because they are an important source of protein, they are not restricted on a low potassium diet. Avoid adding fruit or nuts to main dishes.
For Chinese food
Choose lower-potassium vegetables such as snow peas, string beans, water chestnuts, bean sprouts and bok choy.
Typically, the potassium level becomes low because too much is lost from the digestive tract due to vomiting, diarrhea, or excessive laxative use. Sometimes too much potassium is excreted in urine, usually because of drugs that cause the kidneys to excrete excess sodium, water, and potassium (diuretics).
If hyperkalemia comes on suddenly and you have very high levels of potassium, you may feel heart palpitations, shortness of breath, chest pain, nausea, or vomiting. Sudden or severe hyperkalemia is a life-threatening condition. It requires immediate medical care.
Nearly all of the potassium in your body is found in with cells (in bodily fluids like plasma, blood, and sweat) while the rest is stored in bones. Potassium is mainly regulated by the kidney's and is primarily lost in urine. But you will lose potassium when you sweat. And more sweat equals more potassium lost.
Potassium and exercise
When you exercise, your muscles lose potassium. This creates a substantial rise in blood potassium levels. For most people, the kidneys filter out the extra potassium fairly quickly, and potassium levels return to normal within a few minutes of rest.
Leaching method: Peel and dice potatoes. Place in a large pot of warm tap water and soak for 2 to 4 hours. Drain and set aside.
The U.S. Department of Agriculture's Nutrient Database reports that a 3-ounce piece of cooked, boneless, skinless chicken breast -- approximately half of a whole chicken breast -- contains 220 milligrams of potassium.
Potassium losses from cooking of high-potassium foods can be significant. In the case of spinach for example, potassium levels have been shown to drop from 6.9 to 3.0 grams in 3 and 1/2 ounces of spinach after blanching for several minutes (a loss of about 56%).
A bag of frozen broccoli is always great to have on hand and can be prepared by simply boiling, steaming, roasting, or microwaving (boiling broccoli decreases potassium content). Other reasons broccoli is a superfood: Broccoli is high in many nutrients, including fiber, vitamin C, vitamin K, iron, and potassium.
MYTH #2. MOST COOKING METHODS DESTROY THE NUTRIENTS IN POTATOES. While boiling potatoes does cause a small loss of water-soluble nutrients like vitamin C and vitamin B6, the white potato retains most, if not all, of its potassium and dietary fiber regardless of cooking method, such as baking, boiling, or frying.