I recently received the following question:
Supposedly I am "genetically doomed" to have diabetes even though my blood sugars have never quite gotten into the prediabetic range. However there has been a devastating death toll on both sides of the family from diabetes. What is your opinion of the book, [title of book deleted]?
Remember that part of the reason for publishing books is to make money, and part is to "spread the gospel." What percentage belongs to which part is sometimes difficult to decipher, although sometimes it’s clear that the author has no credentials and hence no credibility. On the other hand, some books, including those published by diabetes organizations such as the American Diabetes Association, can be assumed to represent mainstream thinking rather than off-the-walls nonsense.
If you have a strong family history of diabetes, then indeed you are at risk of getting diabetes someday. This raises the obvious question: can you offset the risk by changing what you eat or in other ways such as taking medications or potions? I could probably write a book myself about this, but will limit myself to this essay.
You indicate that your blood glucose (BG) levels have remained below prediabetic levels, which is good to hear. It’s now understood that there’s no sharp cutoff between normal levels and diabetes levels, and hence an intermediate category of blood glucose has been defined: someone with these in-between levels is described as having "prediabetes." Exact levels for normal vs. prediabetes vs. diabetes depend on whether you’ve eaten recently; if measured before the breakfast meal (which is called a FBG or sometimes a FPG), normal BG is up to 100 mg/dl (5.6 mmol/L), diabetes is 126 (7 mmol/L) or more, and prediabetes is anything in between (100-125 mg/dl, 5.6-6.9 mmol/L). BTW, if several FBG tests are done, and some are 126 or more, then I think most physicians would call the diagnosis diabetes even if others were normal or prediabetic.
(I must digress to discuss briefly an alternate definition for prediabetes that has fallen out of favor. The alternate definition is retrospective, and isn’t very useful: it defines anyone who has a diagnosis of diabetes as ipso facto having been prediabetic before they became diabetic.)
You should be aware that it’s possible for BG to occasionally go above normal, then return to normal: examples of when this might occur is during acute illness, treatment with certain medications (including steroids), or even after extremely large high-sugar-containing meals. Obviously, if you don’t check your BG during these special times, you won’t be aware that it’s been high. So my advice is to ask for a BG to be checked by the lab anytime your physician asks for blood to be obtained for testing for other reasons, and if you are have access to home glucose monitoring, to check during times of acute illness or after huge meals.
You should also have your A1C level checked now and then. This test is not sensitive to recently-eaten food, so can be obtained at any time of the day. If it’s 6.5 or more, it’s compatible with a diagnosis of diabetes; an A1C between 5.7 and 6.4% implies high risk for future diabetes (and hence the label of prediabetes might be applied).
Your question indicated that you wanted to know if there’s any way to prevent prediabetes. I would suggest that most of the recommendations that are given to people who have prediabetes would apply in the scenario of a positive family history:
1) Lose weight if overweight. Note that I don’t recommend any particular diet, nor did I say to avoid sugar. Meal plans can be controversial; I’d suggest that you talk with a diabetes dietitian if possible, and set up a meal plan that you can live with rather than start the latest fad diet that you find in a book or on the internet.
2) Stay physically active, every day if possible.
3) Check your BG and A1C levels occasionally.
4) Be sure that other health problems are looked for, and treated if present, such as obesity, heart disease, hypertension, high cholesterol, kidney disease, and smoking.
5) Start taking aspirin, to prevent heart and stroke problems, if approved by your physician.
There’s one idea that I would not recommend: I would not advise starting prescription medications or herbs or other concoctions that purport to “maintain healthy blood sugar levels.” There’s simply no evidence that prescription medications or anything else will be of any benefit to people without documented problems with blood glucose.
Hope this helps!