By Stephen T. Sinatra, M.D., F.A.C.C., F.A.C.N., C.N.S., C.B.T.

This class of drugs includes Lasix (furosemide), Demadex (torsemide), Bumex (bumetanide), Lozol (indapamide), and HydroDIURIL (hydrochlorothiazide).

Often referred to as “water pills,” diuretics are routinely prescribed by doctors (including me) for patients with a history of heart attack, congestive heart failure, high blood pressure, and edema. Diuretics increase the amount of urine produced by the kidneys, a process technically called “diuresis,” which clears excess fluid from the body and lungs.

The most important use of diuretics is in a scary, life-threatening situation called pulmonary edema, which requires immediate hospitalization. Fluid builds up in the lungs due to a “power failure” in the left ventricle, the left lower chamber of the heart that receives blood and pumps it out under high pressure to the rest of the body—at least that’s what it’s supposed to do. Heart failure or a heart attack can debilitate the left ventricle and then, blood backs up, the lungs fill with fluid, the patient can’t breathe, and bubbles foam out of their mouth. I’ve seen this with dozens of patients. At that critical point, they need oxygen and an intravenous diuretic to push fluid out of the lungs. Once they start urinating, everyone breathes a sigh of relief.

Downsides of Diuretics

Thirty-five years in practice have taught me to be wary of the insidious potential for drugs to deplete or block the absorption of nutrients—and doctors are often unaware of the connection. Important as diuretics are in emergencies, long-term use disturbs the natural physiology of the body, to a degree that may be dangerous. An editorial in the Journal of the American College of Cardiology recently described these drugs as “necessary evils whose use should be minimized as much as possible.”

Here’s the problem: Diuretics cause substantial loss of potassium and magnesium—two minerals that are essential for heart health. Taking a diuretic is akin to opening the flood gates of a dam. You reduce water volume, which is a beneficial effect, but you also lose a lot of the good things in that water. Over time, the result is mineral wasting—a loss of potassium, magnesium, calcium, zinc, and other important minerals that disturbs the body’s physiological balance.

Today, as many as 40 percent of adults over 65 may be taking diuretics on a long-term basis. In people with heart failure, diuretics are used to prevent fluid buildup in the lungs. For high blood pressure, the strategy is to reduce the amount of fluid flowing through the blood vessels and thus, the pressure against the arterial walls. During my first few weeks of medical practice, I put a woman on a diuretic for blood pressure and she developed such potassium depletion that she could hardly move for three days.

I believe that long-term use of diuretics will be increasingly challenged and eventually discouraged because of the mineral-wasting risks. The famous government-sponsored Multiple Risk Factor Intervention Trials (MRFIT, or “Mr. Fit” studies) of the 1970s and 1980s showed that men treated routinely with diuretics had a higher incidence of death despite lowered blood pressure. This development contributed to the subsequent introduction of potassium-sparing diuretics because low potassium could predispose someone to a cardiac arrhythmia. However, those newer drugs didn’t account for the loss of other minerals. Magnesium loss, for instance, may be one factor leading to heart dysfunction.

Vitamin B1 (thiamine) is another important nutrient that may be depleted by diuretics. Symptoms can include depression, reduced mental alertness, fatigue, muscle weakness or cramps, stomach troubles, and in severe cases, difficulty breathing.

Side Effects

Many of my patients have reported night-time muscle cramps and weakness, the result of diuretic-induced mineral loss and thiamine deficiency. Other side effects include dry mouth, excessive thirst, lethargy, drowsiness, restlessness, low blood pressure, abnormal heart rate, gastrointestinal problems (upset stomach, nausea, vomiting, abdominal discomfort, diarrhea), rash, dizziness, and headache.

Potassium-sparing diuretics, such as Amiloride (also referred to as Amiloride hydrochloride or Amiloride HCI), can also cause some of the same problems as regular diuretics, as well as loss of appetite, mental confusion, fever, and impotence.

Nutritional Support

If you’re on a diuretic, be sure to tell your doctor if you develop any of the side effects I just mentioned. In most cases, they can be reduced by dietary and nutritional support. Here’s what I recommend:

  • To offset the loss of minerals and thiamine, take a good multi-vitamin and mineral supplement with thiamine and other B vitamins.
  • Minimize processed or fast food, which is high in salt and woefully low in potassium and magnesium.
  • Avoid coffee and alcohol as these also deplete potassium and magnesium.
  • To counteract depletions, include these foods in your diet: raisins, prunes, apricots, papaya, dates, avocados, bananas, strawberries, watermelon, cantaloupe, oranges, beets, greens, spinach, peas, squash, tomatoes, mushrooms, baked potato, beans, peas, turkey, fish, and chicken.
  • Take 400–800 mg daily of a broad-spectrum magnesium supplement (preferably with magnesium glycinate, orotate, citrate, and taurinate) and eat plenty of magnesium-rich green, leafy vegetables and whole grains.
  • Get 3 grams daily of potassium. The mineral is more challenging to take as a supplement because a potassium pill contains no more than 99 mg, about the amount in two bites of a banana. Eat these foods to reach the daily potassium goal of 3 grams: sweet potato (700 mg), cooked or raw beet greens (½ cup = 650 mg), baked potato (600 mg), coconut water (1 cup = 600 mg), plain yogurt (8 oz = 580 mg), prunes (stewed ½ cup = 400 mg) and prune juice (¾ cup = 530 mg), carrot juice (¾ cup = 517 mg), halibut (3 oz = 490 mg), lima beans (½ cup = 484 mg), winter squash or soybeans (½ cup = about 445 mg), banana (420 mg), spinach (½ cup = 419), dried peaches or apricots (¼ cup = 400 mg), and lentils (½ cup = 365 mg).

As part of my daily routine, I blend a variety of fruits and vegetables and coconut water, for a solid serving of potassium as well as magnesium.

Other Options

For people with mild fluid retention, I recommend drinking a cup of ginger tea daily. Organic ginger tea is available in health food stores. You can also make your own from ginger root: Chop the root into small pieces and boil for about five minutes. However, for anyone who has seriously weakened left ventricle function, there is no substitute for diuretics.


  • Gottlieb SS. Diuretics: are our ideas based on knowledge? J Am Coll Cardiol. 2011;57(22):2242–2243.

This article originally appeared in the Aug. 2011 issue of Dr. Sinatra’s monthly written newsletter, Heart, Health & Nutrition. HMDI has reprinted this article with permission from Healthy Directions, LLC (© 2011 Healthy Directions, LLC).

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