In the final article on the natural supplement inositol, I examine the evidence as to whether it can help treat impotence, lung cancer, and psoriasis. Three big-time conditions indeed.
Impotence affects over 20 million men in the U.S. Multiple factors can cause it, including physical (e.g. heart disease, high blood pressure, diabetes, medications) and psychological (e.g. depression, anxiety, stress).
There is one study that shows that inositol is effective in this condition. This study was conducted in Italy, involving 176 patients with type 2 diabetes randomized to receive four grams of inositol plus 400 micrograms (mcg) of folic acid or placebo. Myoinositol-treated individuals improved their IIEF-5 (a commonly used scale to assess efficacy of treatment of erectile dysfunction) score from a baseline of 12 to 20. They concluded that a myoinositol/folic acid combination deserves consideration as a therapeutic agent for preventing and treating erectile dysfunction in diabetic men for many reasons, the most potent of which is that they have no protection otherwise.
Psoriasis is a common skin condition characterized by thick silvery scales plus itchy, red patches. The cause is unknown, but it is most likely related to the interaction between the immune system and the environment in genetically predisposed individuals. Some of the known environmental triggers include stress, cold weather, alcohol, infections, sunburn, and certain medications.
One study on inositol shows benefit in this setting. This UK study involved 15 patients with psoriasis randomized to receive inositol or placebo in a crossover design and compared to 11 patients not on lithium. Inositol had a significant beneficial effect in those patients on lithium, but no such effects were seen in those not on lithium.
How about lung cancer? In a Canadian study, 16 smokers (40 to 74 years old) with long history of smoking with early precancerous lesions in their bronchi were first enrolled in a one-month myoinositol study to determine the maximal tolerated dose (12 to 30 gram a day). Then they were followed by 10 new subjects on this maximal dose for three months. Results show:
- The maximal tolerated dose was 18 grams a day.
- Myoinositol led to a significant regression of preexisting precancerous lesion as compared to placebo: 91% vs. 46%.
- Myoinositol led to a fall in both systolic and diastolic blood pressure, by 10 mmHg.
- Adverse reactions to myoinositol were considered mild mainly due to gastrointestinal symptoms.
Thus it seems that inositol could help those who have developed lesions protect themselves from cancer.