Potassium Rich Diet
by Sue Kira, Naturopath & Clinical Nutritionist
Potassium is an essential mineral used to maintain electrolyte and fluid balance in the body to keep the body hydrated. It is an essential mineral found mainly in the intracellular fluids (fluid inside cells) with only a small amount in the extracellular fluid (outside the cells).
Potassium is the third most abundant mineral in the body, required for the proper functioning of several organs including the heart, kidneys, brain and muscular tissues.
Potassium is necessary for normal growth, to stimulate nerve impulses for muscle contraction, and to preserve the acid/alkaline balance of the body fluids, with potassium being alkaline. Potassium also helps keep the skin healthy and assists in the conversion of glucose to glycogen, which is how glucose is stored in the liver. It functions in cell metabolism, enzyme reactions and the synthesis of muscle protein from amino acids and stimulates the kidneys to eliminate poisonous waste from the body.
Potassium is rapidly absorbed by the small intestine from our food and drinks and is excreted mainly through urination and perspiration. The kidneys maintain potassium levels due to their ability to filter and excrete potassium as needed.
Because potassium and sodium must be in balance, the excessive use of salt (sodium) depletes the body of potassium by osmosis (transfer of fluids) which is excreted via the urine.
Benefits of Potassium
Cramp alleviation and prevention
Muscle cramps are a common side effect of low potassium levels (along with magnesium) so consuming high potassium foods will help to decreased muscle cramping and improve muscle strength. If an athlete becomes dehydrated and does not consume enough potassium rich foods before and after exercise, they will have a higher risk of cramps and muscle fatigue.
Potassium is a great electrolyte in the human body. Electrolytes are minerals such as potassium, sodium, magnesium and calcium that help to maintain fluid balance inside and outside of our cells. Electrolytes also help to transmit electrical charges throughout the body including the brain and nervous system, so extra electrolytes keep everything functioning faster and more efficiently in the body.
Apart from calcium, bones need other minerals, one of which is potassium. Without adequate potassium, bones can become more brittle. Several studies have found a relationship between increased bone density and increased intake of dietary potassium, even in post-menopausal women and older men.
Reduced Cellulite Appearance
Cellulite is caused by excess fluid and toxins trapped in fat cells, often held there by excess sodium which draws fluid to the cells, whereas potassium helps to flush excess waste out of your cells, so by consuming potassium rich foods you may help to reduce the appearance of cellulite.
Reduced Risk of Stroke
Studies have shown that people with a high potassium diet rich in fruits and vegetables have a lower risk of stroke and reduced blood pressure risk. This is especially true if the potassium rich foods are not accompanied by a high sodium (added salt) diet.
Stabilizes blood sugar
Potassium helps to stabilize blood sugar levels. A decrease in blood potassium levels contributes to a drop in blood sugar. Decreases in blood sugar can cause sweating, headache, weakness, trembling and nervousness. Diabetics need to keep their potassium levels normal to reduce the chances of unpredictable spikes and plunges in their glucose and insulin levels in response to what they eat.
Brain function support
Potassium plays a key role in maintaining the electrical conductivity of the brain and dramatically affects brain function, being involved in higher brain functions like memory and learning. Ailments like epilepsy are affected by the dysfunction of potassium channels that can occur from potassium deficiency. These channels can help moderate and regulate electrical currents throughout the body. A potassium channel generates an electrical current, which in turn allows a flow of minerals to regulate the neurotransmitters in the brain and nervous system.
Potassium channels help to boost the efficiency of nerve reflexes that transmit messages from one body part to another. This in turn helps in muscle contractions to perform various activities every day.
Potassium assists in the metabolic processing of various nutrients like fats, proteins and carbohydrates which have an impact on tissue regeneration, cell growth and an overall balanced metabolism, as well as support the extraction of energy from food.
Reduce anxiety and stress
Potassium can help regulate various hormones in your body, including stress hormones like cortisol and adrenaline, which can both trigger anxiety and a higher stress response. Anxiety and stress are very detrimental to our health, so a diet rich in potassium can be a great support.
Prevents fluid retention
Another significant role that potassium plays is the maintenance of optimal fluid balance in our body. Potassium helps to put fluid inside cells where it is needed. On the other hand, sodium (salt) draws fluid and potassium out of cells, creating dehydration of cells and a flood of fluid outside of the cells leading to oedema (fluid retention).
Different types of cells require a different water balance to function efficiently and potassium helps these cells to regulate the balance.
An optimum fluid balance for our cells keeps our organ systems functioning efficiently, which is why many people recommend eating potassium rich bananas and/or oranges to rehydrate during and after sporting events, or even after a heavy night of drinking.
A deficiency of potassium may cause nervous disorders, constipation, insomnia, muscle damage and irregular heartbeat. When a deficiency of potassium impairs glucose metabolism, energy is no longer available for the muscles and they can even become paralysed (in severe cases) or work less efficiently, giving rise to poor reflexes, impairment of neuromuscular coordination and soft sagging muscles. In teens it can result in acne and for older people, dry skin may occur.
Alcohol and coffee increase the excretion of potassium. In fact, alcohol is a double antagonist (inhibits absorption) as it also depletes magnesium reserves. Magnesium is needed to hold potassium in the cells.
Potassium deficiency symptoms can also include severe headaches, dehydration, heart palpitations and swelling of glands and tissues. Also, potassium deficiency can lead to:
- Cellulite build-up
- Weight gain
- Increased blood pressure
- Muscle cramps
Causes of low potassium
- Endurance cardiovascular exercise without proper hydration
- Diet low in fruits and vegetables
- Diet high in sodium salt or processed foods
- Use of diuretics
- Consumption of alcohol, coffee, tea or other caffeinated substances
Potassium rich foods can be a great addition to most diets, but if you choose to take potassium supplements on top of your diet, first consult your doctor or health practitioner.
Signs and symptoms of excess potassium
Excess potassium can occur for people who have kidney disease or are on dialysis. Dialysis filters the blood but cannot properly process potassium, meaning dangerously high levels of potassium may accumulate, which can lead to heart disease, muscle paralysis, trouble breathing, tingling in the hands and feet, heart arrhythmia and nausea.
For most people, an overdose of potassium from natural (food & drink) sources is extremely rare, but it is possible to consume too much potassium via supplementation which can lead to nausea and vomiting and extra stress on the kidneys.
Potassium rich foods
The recommended daily allowance (RDA) for potassium is between 3,500 – 5000mg depending on your age, individual needs, exercise levels and health condition.
Food sources of potassium include all vegetables, especially leafy greens, plus oranges, sunflower seeds and mint leaves. Large amounts of potassium are also found in potato skins and bananas, as well as coconut water. Here are some specific quantities:
- Avocado (whole): 1 = 1070mg
- Spinach (cooked): 1 cup = 840mg
- Sweet potato (medium): 1 = 950mg
- Dried apricots: ½ cup = 755mg
- Dates: 1 cup = 1170mg
- Raisins: 1 cup = 1086mg
- Sunflower seeds: ¼ cup = 240mg
- Prunes (stewed): 1 cup = 800mg
- Cacao: 1 tablespoon = 80mg
- Pumpkin/winter squash (cooked): 1 cup = 900mg
- Salmon: 200g/7oz = 850mg
- Flounder: 200g/7oz = 1170mg
- Coconut Water: 1 cup = 600mg
- White Beans (cooked): ½ cup = 500mg
- Lentils (cooked): 1 cup = 730mg
- Mushrooms: 1 cup = 430mg
- Banana (large): 1 = 420mg
- Oranges: 1 = 180mg
Before you commence your diet, see your medical or health care professional for qualified guidance about what foods and supplements are best for your body. While on the diet do not stop any medications or supplements previously prescribed unless advised otherwise by your medical or health care professional.
During the early stages of a new diet, you may experience symptoms such as fatigue, headaches, or body aches, which may occur because your body is detoxifying. However, if you are unsure about a symptom at any time, check immediately with your medical or health care professional.