Fenugreek may be appropriate for certain individuals, but it may be dangerous for women of childbearing age, Dr. Shane-McWhorter stressed.
Bitter Melon
This pickle-like vegetable from Southeast Asia and South America contains the hypoglycemics momordin and charantin, the alkaloid momordicine, and polypeptide P. It is thought to promote glucose uptake and glycogen synthesis.
It has a long list of reported side effects, including diarrhea, possible spontaneous abortion, and favism (acute hemolytic anemia) in individuals with hereditary glucose-6-phosphate dehydrogenase deficiency. Interactions have been reported with sulfonylureas and may occur with potassium depleters.
The largest study done with bitter melon (Momordica charantia) involved 100 patients with type 2 diabetes who ingested an aqueous suspension of the vegetable pulp after measurement of their fasting plasma glucose, which averaged 160 mg/dL. At 1 hour, glucose had dropped to 131 mg/dL. Following a 75-gram oral glucose load, mean glucose levels dropped to 222 mg/dL, compared with a mean of 257 mg/dL measured the previous day (Bangladesh Med. Res. Counc. Bull. 1999;25:11–3).
This agent should also be used with caution in women of childbearing age and should not be used during pregnancy, due to the risk for bleeding or contractions.
Ginseng
Both the American and Asian versions of ginseng are in the steroid family of ginsenosides, which have various hormonal and central nervous system effects. Depending on which ginsenosides they contain (Rg1 vs. Rb1), they can either increase or decrease blood pressure and CNS activity.
Reported side effects include the “ginseng abuse syndrome,” characterized by hypertension, anxiety, and insomnia. Ginseng has also induced postmenopausal vaginal bleeding, and it interacts significantly with a long list of drugs including warfarin, diuretics, β-blockers, antipsychotics, antidepressants, and opiates.
In one randomized, controlled, multicenter trial, 36 patients with type 2 diabetes were given 100–200 mg ginseng or placebo daily for 8 weeks. Results included improvements in mood and psychomotor performance, as well as lower A1c and FBG levels (Diabetes Care 1995;18:1373–5).
American ginseng appears to lower glucose better than does the Asian type, but few studies have been done in diabetic patients. Of concern are data from a U.S. analysis of 25 different commercial preparations of ginseng in which the actual quantities varied from 12% to 137% of what was indicated on the bottle (Am. J. Clin. Nutr. 2001;73:1101–6).
Patients who choose to take ginseng should do so within 2 hours of a meal to avoid hypoglycemia. To avoid hormone-like effects, some have suggested taking a 2 week holiday every 2–3 weeks, or limiting its use to 3 months, Dr. Shane-McWhorter said.
Aloe
A member of the lily family, aloe's dried leaf juice was once used as a laxative ingredient, but that was stopped because it sometimes led to electrolyte depletion and intractable diarrhea. The gel component, however, is still used as a topical wound treatment and internally for diabetes. Its mechanism is thought to be related to its high fiber content.
In one single-blind, placebo-controlled study, FBG dropped from 250 to 142 mg/dL in 40 patients newly diagnosed with type 2 diabetes who took one tablespoon of aloe gel twice daily for 42 days, while FBG increased in the placebo group, from 251 to 257 mg/dL. Triglycerides also dropped in the aloe group, but there was no change in total cholesterol. (Phytomedicine 1996;3:241–3).
In another study of 40 patients already taking the sulfonylurea glibencamide, 20 were also given aloe for 42 days. Again, aloe reduced FBG from 288 to 148 mg/dL compared with 289 to 290 mg/dL with glibenclamide alone (Phytomedicine 1996;3:245–8).
Although the data on aloe at this time are too limited to support its use as a treatment for diabetes, it is one of the most popular alternative diabetes remedies among Hispanic patients. If they choose to use it, the dosage is 50–200 mg/day of the leaf gel, not the cathartic (leaf juice) form.
Nopal
The fiber in this member of the cactus family is thought to decrease glucose absorption and possibly increase insulin sensitivity. Also known as “prickly pear,” it's usually eaten cooked, and is also used to treat hyperlipidemia and to prevent hangovers. Side effects include increased stools and abdominal fullness, as well as possible additive hypoglycemia with secretagogues.
In one study, 16 patients with type 2 diabetes were assigned to broiled nopal (Opuntia streptacantha Lemaire), 10 to water, and 6 to broiled zucchini. At 2 hours, mean glucose dropped from 222 to 198 mg/dL and to 183 mg/dL by 3 hours (Diabetes Care 1988;11:63–6). In another study by the same group, nopal combined with sulfonylurea produced a 41-mg/dL drop in glucose at 3 hours, versus no change in those given water (Diabetes Care 1990;13:455–6).