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Q: Protease Inhibitors & Cholesterol
I was interested in Jennifer's article on fat Figuring Out Fat, since I recently had a heart attack due to increased lipids from taking protease inhibitors. I was surprised she recommended coconut oil. This is a saturated fat, and should, I think, encourage cholesterol plaque buildup. Could you help me understand the point? I love Thai food, which has coconut milk. Thanks.
A: Ken Stringer (Website Administrator) responds:
Just a preamble from me, the administrator, before the Virtual Faculty speaks. Elevated cholesterol numbers due to Protease Inhibitors (PIs) are a relatively recent development. Since they came dramatically on the scene in 1996, after Jennifer's "Figuring Out Fat" was written, much has been learned about the effects, intended and unintended, of PIs. Jennifer was able to deal with this "sea change" in HIV/AIDS nutrition only in the last few months of her life when she made some pertinent revisions in her advice on this subject in the last two articles she wrote. I'll let her speak for herself in these 1997 excerpts from Upside Down Nutrition:
It's not at all difficult to turn to the "popular press" and find dietary advice for prevention of common deadly disorders like heart disease and cancer...but with HIV there's historically been little risk of either, except for immune-related cancer like Kaposi's Sarcoma (KS) and some lymphomas (glandular cancers). But now, with protease inhibitors sometimes driving up cholesterol numbers, there's some need for HIV-specific cholesterol-lowering advice. While it's easy to find information on cancer-nutrition, and cholesterol-nutrition, you probably won't find advice that incorporates these with the specific needs for appropriate HIV-nutrition.... Until the advent of protease inhibitors, HIV healthcare workers have worried about cholesterol levels only if they dropped too low!
In my private practice, I've seen cholesterol totals as low as 86, a really low lab level! As a reference, for Negative Normals (people who are not HIV+) we want to see total cholesterol numbers to be under 180 and we really worry if the report reads 220 or higher. Now, as I check over labs for my protease clients, I'm seeing up to 250 and higher(!), even though dramatically lower labs from long ago reside in the same person's chart. In fact, when I first wrote a version of "Upside-Down Nutrition" in 1994, I made the comment that "Cholesterol is the last thing to worry about for Positive People." My how things can change!
Obviously, I can't say that now... [That's why] I recommend reading the current monthly [HIV/AIDS] newsletters and magazines. And read them each time they come out (so to speak), to make sure that what you think is right, is right. As science brings us closer to expecting to celebrate future birthdays and things like that, we have to look at the things that these new scientific findings do to our overall picture of HIV and its many devious ways... I think everyone communicating information to an HIV-Positive audience has to be extremely current with their information, or it could cause harm. And harm in healthcare is not acceptable.
And that is why this website has a Virtual Faculty: To keep current and up-to-date. So here's the latest:
Chester Myers, PhD, MS responds:
While coconut fat is mainly saturated, it does not contain cholesterol as do animal saturated fats. Furthermore, coconut fat is about 65% medium chain length fatty acids, which are generally not candidates for involvement in the chemistries that result in high triglycerides (TGs). However, there are data from (arguably, poorly controlled) studies that indicate that saturated fats may encourage a "bad" form of cholesterol (LDL) that has an enhanced tendency to cause plaque formation. It is therefore possible that coconut fat could be a source of modest pressure towards an unfavourable imbalance of the TGs and cholesterol. However, it is oxidized cholesterol that most strongly carries this distinction. Thus, maintenance of a high intake of antioxidants is an important consideration. (Examples of common antioxidants are Vitamins C and E; the carotenoids, including beta-carotene, from natural sources; selenium; and others. See Jennifer's articles Alphabet Soup and Phytochemicals for a fuller discussion of antioxidants and other vitamin and mineral supplements.)
I'm a scientist, so bear with me while I wax scientific for a minute. There is currently no evidence that the elevated cholesterol with protease inhibitor (PI) use derives from increased formation of cholesterol in the body, or from dietary intake. We know that PIs interfere with cytochrome P450 enzymes. It is a section of this class of enzymes that convert (with help from vitamin B3) cholesterol to bile acids/salts, a major mechanism for removal of cholesterol from the body. It is reasonable to assume that many drugs, including PIs, inhibit this conversion, resulting in excessive buildup of cholesterol in the body. A wealth of evidence indicates many of the adverse effects (gastro-intestinal problems, essential fatty acid defects, imbalance in testosterone and its dihydro form, etc.) of multiple drug regimens derive from interference with P450 enzymes (CYP11, CYP17, CYP19 and CYP21), especially those enzymes of the adrenals, testis and ovaries. Unfortunately, this particular group of P450 enzymes seems not to be examined by pharmaceutical companies in their testing procedures. Indeed, there has been little research in this area regarding drug use.
If, for whatever reason, both TGs and cholesterol are elevated, it would seem wise to "pull out all the stops", and not to gamble. Coconut fat, in this case, would best be avoided. Also, since ritonavir carries the greatest likelihood of P450 interferences, it may be wise to minimize saturated fat intake as a prophylactic measure with this PI (perhaps to slow the onset of elevated TGs &/or cholesterol). Otherwise, coconut fat can be an easy source of calories that bypasses the carnitine pathway. But, we must first ensure adequate intake of the essential fatty acids (both n3 and n6 types commonly known as Omega-3s and Omega-6s).
Use of monounsaturated fats such as found in olive and canola oils would be a good choice for the major dietary fat intake after the essential fatty acids. Indeed, canola oil, but not olive, will supply the essential fatty acids as well as monounsatured fat, while being a low contributor to saturated fats. Avoidance of high intakes of the trans fats may be more important than avoidance of saturated fats, though we don't have enough information yet to make a definitive informed decision. (Trans fats, by the way, are found in hydrogenated forms of unsaturated oils, common in margarine and a variety of baked goods [read the labels]. Saturated fats cannot exist in a trans form, so there is no worry of trans forms from them.) Several servings per week of fresh fish (which are a good source of the Omega-3s) would also be a good way to moderate buildup of TGs and cholesterol. Supplements of fish oil may be okay provided trans fat contents are low. Processing (such as deodorization) of fish oils may form higher levels of trans fats than are formed by the processing of vegetable oils (like flax seed), and because of this I am leary of general recommendations for use of fish oil supplements. The fish itself is better.
Thus, while encouragement of coconut fat as a high proportion of dietary fat intake was reasonable before HAART (Highly Active Anti-Retroviral Therapy) programs, I think this fat should now be used with caution and discretion by those taking combinations of several drugs that interfere with P450 enzymes. Although there are no compilations of drug-drug interactions for the P450 enzymes that are in question here, an indication of potential interactions is available from tables for other P450 enzymes (especially, the CYP3A4, CYP2D6 and CYP2C9/19 enzymes of the liver) available at hivinsite.ucsf.edu. Perhaps of equal concern is that there are no tables for relevant drug-food interactions. Unfortunately, food components such as common bioflavonoids (quercetin, also called quercitin, is the most common, but there are others) that would otherwise be expected to be beneficial for cholesterol control, may be major sources of drug-food interactions.
As with most of human nutrition, few recommendations are possible from proven facts. We are left to rationalize "reasonable recommendations" from available information. It is important to keep one's ear to the ground for further information.
Diana Peabody, RD responds:
A further comment on this question. Saturated fats do not have to be avoided altogether but can make up about 10% of calories (for a man who gets about 2500-3000 calories this means about 25-30 grams of fat from saturated fat per day). Some of this could be from the coconut fat. Trans fatty acids also need to be limited and are likely as bad as saturated fats ( maybe worse) for increasing the risk of cardiovascular disease. These are found in hydrogenated oils which should be on the labels of foods. Common ones are snack foods, margarine, crackers, some peanut butters. It is worth reading the labels for this one.
Antioxidants have proven effective in reducing the risk of heart attack in the Nurses' Health Study (vitamin E in particular @ 200 IU). Also, if you have heart disease better load up on folate, B6 and B12 (i.e. take a good B complex and get B12 shots). I agree with Chester that fish is good. The Nurses' Health Study showed that 2.5 servings per week was protective and that eating the fish was better than taking fish oil pills.
The other key components for keeping the heart healthy as well as for HIV benefits are exercise and quitting smoking! Not really on the topic of coconut fats but worth knowing.
