I frequently get questions about a nutritional connection to muscle cramps. Leg and other muscle cramps come and go so it is difficult to say what might be the cause.
Lactic acid buildup is that feeling in your muscles when you walk up stairs or when you exert yourself beyond being able to catch your breath. The muscles start to ache and it only gets worse when you keep going. Stop for a few minutes and take some deep breaths, walk a little to get the blood circulating again, stretch and the ache goes away. That kind of cramping and muscle ache is caused by an inadequate supply of oxygen to the exercising muscle.
In a similar way, when someone does not drink enough and gets dehydrated, they accumulate excess waste products around the body tissues and muscles and they are not able to get enough oxygen to the extremities. Again, lactic acid builds up and the muscles start to cramp, especially in the feet, legs and hands.
Certain minerals called electrolytes play a major role in the body's electrical system and the contraction and relaxation of muscles. Electrolyte balance in the body is usually well maintained through the hormonal regulation of minerals through the kidneys.
Some electrolytes include sodium, potassium, calcium and magnesium. These minerals are all found naturally in their elemental or isolated form inside food. The body has way of balancing electrolytes to a perfect balance called homeostasis.
When the body needs more of a certain mineral, the kidneys prevent the mineral from entering the bladder. When there is too much of the mineral, the kidneys allow it to be transported to the bladder and it is urinated out. Mineral deficiencies, however, can occur with conditions such as excessive sweating, diarrhea, vomiting and regular diuretic use.
Potassium is found in many foods, but is especially abundant in vegetables, potatoes, legumes, certain fruits like melon, bananas and citrus as well as milk, meats, and fish. Magnesium is found naturally in whole grains, spinach, kale, broccoli, legumes and nuts.
Good food sources of calcium include most dairy foods and dark leafy greens. Inadequate stores of vitamin D can lead to a calcium deficiency. This vitamin forms in the body with exposure of sunlight on the skin and supplemental forms of vitamin D is frequently recommended especially in older individuals and those that do not go outside much.
Consuming concentrated forms of any of these minerals can lead to unintended consequences. Taking calcium supplements can build up in your blood vessels causing atherosclerosis, kidney stones and impaired absorption of iron and zinc. Excessive use of potassium can lead to rapid heartbeat and arrhythmias. Too much magnesium from supplement use can lead to muscle paralysis and difficulty breathing.
Excess sodium intake is very common with regular use of table salt and processed foods. Eating too much sodium increases the sodium in the urine while at the same time drawing out other needed minerals along with it. Likewise, too much protein in the diet also increases the excretion of many minerals. Extra dietary protein also requires an increase in fluid intake to help rid the body of waste products.
So muscle cramps can be a result of many factors. The best way to prevent them is to drink plenty of water and eat a healthy diet of wholesome, natural and low-fat foods and to get regular exercise. Taking a general multivitamin is not usually a problem, but avoid excess supplementation without medical supervision.
Chuck Newcomb is a consulting registered dietitian providing medical nutrition therapy services for Memorial Hospital Los Banos. He has a master of science in clinical nutrition from New York University. Email questions to ChuckRD at: MHALosBanos@SutterHealth.org or on his website MySmartRD.com.
Chuck Newcomb is a consulting registered dietitian providing medical nutrition therapy services for Memorial Hospital Los Banos. He has a master of science in clinical nutrition from New York University. Email questions to ChuckRD at: