– Frank, Florida Yes, flaxseed may help lower your sugar levels, and it plays a role in the prevention of prostate cancer as well. However, the strength of the evidence is too weak to permit definitive recommendations. Nonetheless, flaxseed is rich in alpha-linolenic acid (ALA), an essential fatty acid that appears to be beneficial in preventing heart disease and related illnesses. Flaxseed contains the right ratio of omega-3 to omega-6 fatty acids, is high in fiber, and provides a phytoestrogen called lignan, which may have antioxidant properties that protect against certain cancers. There is some evidence that eating flaxseed reduces blood sugar levels after a meal and increases insulin levels because of its high content of soluble fiber. (It is 28 percent fiber, of which two-thirds is soluble.) Indeed, flaxseed carbohydrate (what remains after the oil is removed) was used in a study that showed a beneficial effect. Although this result was not duplicated in other studies, flaxseed has been shown to improve insulin sensitivity. An interesting, yet unproven, potential benefit may be the prevention of type 1 and type 2 diabetes; in animal models, flaxseed has been shown to delay the onset of the disease. Flaxseed might help your prostatic health as well. In fact, the American National Cancer Institute has singled out flaxseed as one of six foods that deserve extensive research. Why? Because flaxseed contains a large amount of phytonutrients that serve as antioxidants, as well as those omega-3 fatty acids, which seem to play a role in preventing the formation of abnormal cells in the body. In terms of your specific question, flaxseed may reduce the prostate-specific antigen (PSA), a protein produced by the cells of the prostate gland that is often used as a marker for cancer. Also, men whose prostatic fluids contain high levels of lignan (the phytoestrogen found in flaxseed) seem to have a low risk of prostate cancer, though study results of this were not conclusive. One word of warning: Flaxseed is high in calories. Here’s an idea of how much you might need to consume to obtain its beneficial effects — 1 tablespoon of flaxseed has 5 grams of fat and weighs 12 grams. You need to take 40 to 50 grams of flaxseed, which is equal to about 4 tablespoons and has a total of 20 grams of fat. Milled flax has 36 calories per tablespoon; flax oil has 124 calories per tablespoon. (Flaxseeds are more nutritious than their oil.) These caloric considerations are important in the control of your glucose level. Stay tuned, as I am sure there will be more studies that will guide us better in using flaxseed to stay healthy. Q2. I am diabetic and a vegetarian. I eat soy bars and shakes sometimes to help me get enough protein. My neighbor says that soy is not good for diabetics. Is this true? Can I continue to use these products? — Phyllis, Florida There is no evidence that soy or soy products cause harm to diabetics. On the contrary, soy and soy products contain bioactive compounds called isoflavones that can enhance cardiovascular health. As a vegetarian, meeting your daily protein requirement of 0.75 grams per kilogram of body weight might be a challenge. Therefore, for now I would recommend that you continue to supplement your protein intake. Q3. I take Amaryl for diabetes. Recently, my doctor prescribed triamterene for high blood pressure, and now my resting blood sugar is much higher. I’ve read the drug information, and it says that this medication “may cause high blood sugar in diabetics.” In that light, why would my doctor prescribe this medication? Is it safe for me to take it? — Linda, South Carolina Neither Amaryl nor triamterene should cause a rise in glucose levels. On the contrary, Amaryl works to reduce them. Triamterene (a type of water pill), however, is often given in combination with thiazide diuretics (another type of water pill), which have the potential to mildly increase sugar levels in people who are prone to or have diabetes. Usually, the benefits of the diuretics (they control blood pressure and can stave off cardiovascular complications) outweigh the risk from the small increase in blood glucose levels. Thiazide diuretics, therefore, are administered frequently to people with diabetes. One possible step to reduce the risk of developing elevated sugar levels when taking these medications is to make sure your potassium level is within the normal limit. The combination of triamterene and a thiazide diuretic (brand names include Dyazide and Maxzide) are given often to prevent potassium from becoming low. If indeed you are taking triamterene alone, you might look for other reasons that will explain the rise in your sugar levels. Q4. I used to check my blood sugar three or four times a day, but then suddenly my doctor said I was testing way too often. Now he only allows me to test three or four times a week. One day it was 374! I had no symptoms. How can I know when or what to eat if I cannot check my blood often? — Kathy, California There is no single strategy for how often diabetics should check their glucose levels. Generally, it is better to check more often than less often, but the frequency can depend on several factors, including your lifestyle, the type and severity of your disease, how variable your glucose level is, how you manage it, and how well it’s controlled. I agree with you that you should check your sugar with a practical purpose in mind. In other words, knowing your values should then help you modify your eating, exercise, and treatment regimen. It is disconcerting to have a sugar level above 300 and not know it, and you should be commended for wanting to monitor your levels closely. If you’re not prone to low sugar levels, your day-to-day activity and the quality and quantity of your food intake do not vary, and your hemoglobin A1c value is less than 6.5 percent, it is okay to check just a few times a week. However, I recommend you check more often, especially in the following circumstances: It is best to check before meals, two hours after each meal, and at bedtime. If your daily eating and exercise habits do not change, and you do not want to check as often, you might consider checking different times on different days. Q5. I drink a great deal of diet soda and have read that it can cause blood sugar spikes in people with type 2 diabetes. Is this true? Should I avoid diet soda? — Karen, Ohio The short answer is that drinking diet soda does not cause a rise in blood sugar level. Some studies have linked artificial sweeteners, such as the aspartame (NutraSweet) used in many diet sodas, with weight gain. Weight gain increases insulin resistance, which leads to an increase in blood sugar level. However, this finding has not been confirmed in other studies. Nonetheless, I would caution you against drinking a “great deal” of soda. First, excessive intake of diet soda might edge out of your diet nutritious alternatives like whole juices, fresh fruits, and other healthy foods that contain essential vitamins and minerals. Second, there is a limit to the acceptable daily intake (ADI) of artificial sweeteners that you should not exceed. The ADI depends on the type of sweetener — 5 mg/kg/day for Splenda (sucralose) on the lower end, and 50 mg/kg/day for aspartame on the higher end. This can represent somewhere between 6 to 18 12-ounce cans of diet soda for a person weighing about 150 pounds, or 68 kg. Also, remember that other low-calorie or no-calorie food products that you may be eating also contain artificial sweeteners. While you may not reach the level of intake that is considered unsafe, as it is 100 times more than the above limits, all the effects of artificial sweeteners in people with diabetes have not been studied enough to be considered completely safe. Some diet sodas also contain caffeine. Sodas such as Diet Mountain Dew contain up to 55 mg of caffeine in a can, and the majority of diet sodas have about 40 mg of caffeine. Just to give you a comparison, a cup of espresso contains about 100 mg of caffeine. I mention this because there has been a recent focus on caffeine’s effect on insulin sensitivity. Insulin sensitivity is a measure of how well your body responds to a glucose load, for example, after a meal. Decreased insulin sensitivity is a diminished ability to metabolize glucose efficiently after a meal, leading to a high after-meal sugar level. Experiments have shown that 350 mg of caffeine in a person weighing 70 kg (154 pounds) can reduce insulin sensitivity by 15 percent. This is more than six cans of diet soda drunk consecutively. The take-home message here is that while there is no conclusive evidence that consumption of diet soda in moderation raises blood sugar, excessive intake might have a negative health effect. There is a call for studies that will convincingly determine the effect of artificial sweeteners on glucose metabolism. So stay tuned — but in the meantime, I would advise you to scale back on your diet soda consumption. Q6. I have type 2 diabetes and enjoy red wine. Is it okay to have two glasses of wine per evening? — Ann, California Not everyone’s wine glass is the same size. If you do not exceed a total of seven five-ounce drinks per week, you may continue to enjoy your wine. However, you should drink any alcohol with food and make sure that you do not experience hypoglycemia (low blood sugar) after drinking. Hypoglycemia can occur up to one hour after drinking. You should also factor in the calories in wine in your daily caloric requirement. Five ounces of red table wine contains about 129 calories, and white wine contains about 119 calories. If you drink two five-ounce glasses of wine at a time, you will add 238-258 calories to your daily intake. Learn more in the Everyday Health Type 2 Diabetes Center.
