In Part One we were on a tirade about how fishy it seems that dietary fats are often lumped together as a single entity and demonized. Across-the-board condemnation of dietary fat is like branding all drugs as bad... or all people of a particular ethnic background as undesirable. I suppose we could call the media hype against fat "nutritional racism."
The fact that a specific individual wrongs you doesn't give you the right to extrapolate ill will to all those of his ilk. Some individuals may be more than willing to help you. So let's get into what I call "special lipids," those which offer benefits at just a few grams per day or less.
Fish oils, in particular are very helpful. DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid) are definitely good guys. They are metabolized to form prostaglandins and thromboxanes (the 1- and 3-series) that are less inflammatory and platelet aggregatory, for example, than those resulting from common linoleic acid metabolism (the 2-series). That alone is good news for athletes who suffer chronic tendonitis, bursitis, and may even have high hematocrits/ increased blood viscosity/ low HDL due to androgen use. Cultures like the Japanese and Greenland Eskimos (20, 41) have slower clotting times, better serum cholesterol, lower risk of heart disease and less diabetes – at least in part due to their reliance on marine oils.
And we're not just talking prevention. Persons with chronic inflammatory diseases have actually benefited greatly from treatment with fish oils (less joint stiffness, pain, inflammation, etc.).(12, 15, 27, 56) Fish oils can actually replace arachidonic acid (an inflammatory metabolite of common linoleic acid) in cell membranes – like a bouncer giving the boot to a troublesome patron.(25, 49, 51)
Supplementation studies have used up to 18 grams daily (20), often with a dose-response kind of scenario (more being better, considering the desirable omega-6: omega-3 ratio), even though the recommended "safe" daily amount is three grams.(39) Amazingly, this is a true example of a mere food item performing the same task (altered cyclooxygenase function and prostaglandin synthesis) as an honest-to-God drug (e.g. aspirin).
If we let the conspiracy theory proposed in Part 1 run wild, we might even speculate that drug company lobbyists have held a longstanding role in down-playing such juicy knowledge. (Not that I believe this, but there is less money to be made when consumers can reduce the need for drugs via cheap foods.)
Reduction of inflammation and the body's associated acute phase response is about more than pain; it's also about anti-catabolism. Fish oils have shown promise here too. Persons with both cancer cachexia and post-surgical wasting have benefited from DHA and/ or EPA. Both immunological catabolism and poor appetite are corrected. (4, 19, 21, 29, 42, 53, 57) This can result in weight gain (19), just as is seen in preterm infants fed DHA.(22) Yet it's unlikely that the growth improvements are due to fat deposition.(3, 45) If you've read my stuff before, you know that the injurious, catabolic phase following intense lifting has real (albeit reduced) similarities to such maladies. Thus, the anti-catabolic nature of fish oils alone is probably worth their inclusion into the bodybuilding lifestyle. And let's not even get into diabetes, hypertension, depression and other conditions positively affected by fish oils. Better health, itself, is another reason to eat your salmon and/ or take your fish oil. We all need to be reminded sometimes that bodybuilding is about well-being as well as raw muscular size and leanness.
Very long chain, highly unsaturated fatty acids like EPA (20 carbons long, five double bonds; omega-3 type) not only alter prostaglandin and thromboxane "balance," they also (and even independently) alter cell membrane fluidity. Not all of the effects of such "good guy" fats stem from eicosanoid metabolism.(41) The increase in fluidity could alter nutrient entry, toxin efflux, and even the time course of muscular repair.
Indeed, fish oils have been shown to acutely exacerbate the release of creatine kinase (CK) after eccentric (lengthening, damaging) contractions.(16, 17) Other types of fat may too. (See Figure 1. below.) I subscribe to the theory that this is not always indicative of more damage, but rather of increased cellular permeability and turnover (and subsequent repair); you know, "out with the old; in with the new."
Removal of damaged muscle-cell components is a necessary step in the rebuilding process. Older folks, for example, don't dump as much CK after intense exercise as their younger counterparts (16) – which is symptomatic of impaired, not improved, recovery. Certainly, the older individuals aren't more resilient to injury simply because their CK levels are lower. More likely, they're having a harder time removing the damaged "debris" than their younger counterparts. Below are some data of my own that fit this whole "lipid / cell membrane / CK" scenario:
Figure 1. ref 35.
Which brings us to conjugated linoleic acid (CLA). This lipid class is actually a series of trans fatty acids (cis9, trans11 and trans10, cis12 double bond types, among other isomers) that possess unusual properties. (Not all trans fats are "bad".) Potential benefits include muscle growth/ preservation, improved glucose tolerance, nutrient partitioning, and prevention of fat gain.(9, 44)
Unfortunately, several years after the wide-spread commercial introduction of CLA, most of these exciting effects have only been documented in animals, although this is slowly changing. My contention is that unless researchers are satisfied helping rodents everywhere live long, healthy lives, we need more human work with this class of lipid.
My colleagues and I have made measurements indicative of CLA-induced increased anabolism and strength in novice bodybuilders (34), as well as reductions in a catabolic cytokine (interleukin-6) and reduced soreness post-exercise with no evidence of overt toxicity.(35) There's also data coming to light regarding reduced body fat (40), although I've yet to see this in already-lean bodybuilders.
And it should also be noted that not all research on CLA has shown significant results (28) despite moderately large "effect sizes" (potential treatment effects). Contrasting results could be related to the dose, measurements, and duration of the intervention. Overall, the data continue to look promising (9), suggesting that CLA may be particularly effective as a partitioning agent during periods of overfeeding when adipocyte (fat cell) filling is otherwise in high gear.(44) "Bulking" phases and holiday overeating come to mind.
Yet, as with all lipids, changes come slowly. "Special fat" supplementation is nothing like ephedra or creatine consumption, where there's an acute, feel-able result; that's simply not how lipids are metabolized. It generally takes a few weeks just to get substantial tissue incorporation, after which physiological changes can occur. I don't expect athletes who are into immediate gratification to rave about CLA or any other specialty lipid. To summarize CLA, I think it's safe to say that, unbeknownst to many bodybuilders, research on CLA is still burgeoning and that's not something that happens with worthless compounds.
But let's move on to other fascinating lipids. Evening primrose oil is a great source of gamma-linolenic acid (GLA). Black currant seed oil and borage oil are too, but the latter is sometimes avoided as having toxic aspects and no greater efficacy despite its higher concentrations of GLA. (Actually, it's the borage seeds that may contain liver toxins and the commercial oil is reportedly free of them.) The researched benefits of GLA range from reduced estrogen receptor expression (26) to DHT inhibition (30, 31) to pharmaceutically-potent anti-inflammatory effects (38, 48, 56).
With a little creative speculation, these effects could extend to an improved endocrine profile and immune-mediated anti-catabolism for bodybuilders. In any case, the risk-to-benefit ratio is favorable considering GLA's low toxicity.(58, 7) GLA is even (flippantly) referred to as the "Elixir of Life" in one of my biochemistry texts (48) because of its legitimate promise. Since various conditions (e.g. diabetes, aging, alcoholism, premenstrual syndrome, rheumatoid arthritis, cancer, cardiovascular disease) and even genetic predispositions can result in suboptimal PUFA metabolism (deficient delta-6 desaturase activity), GLA – which skips the deficient step – may indeed cause widespread metabolic changes.
Garlic and its oils have also been the focus of considerable research, too. Effects that would interest athletes include increased Testosterone, decreased cortisol, and improved nitrogen balance in rats, (43) reduced blood glucose in men, (59) improved feed efficiency and weight gain in hamsters (32) and enhanced total antioxidant activity in humans and animals (32, 59). Again we the see the (dietary oil-associated) improved endocrine response. And although it depends on one's initial levels, blood lipid improvements may also occur (60), along with purported pro-circulatory effects and reduced blood clotting (14), all of which have led to worldwide use of garlic to combat heart disease.(1) These latter effects should be of interest to any health conscious person. So, in short, eat your garlic and garlic oil; even if your breath will be kicking like Bruce Lee.
Next up: common, but healthy fats. Monounsaturated fatty acids (oleic acid in olive oil, canola oil) and linolenic acid (the "other" omega-3 fatty acid present in flax oil, soybean oil) also have apparent benefits. Monounsaturates are among the most potent/ healthy/ cheap anti-oxidant agents one could buy. There are plenty of examples of their anti-oxidative properties.( 5, 10, 11, 13, 46, 50) They've also been shown to reduce blood pressure, enhance glucose tolerance, and improve blood lipid profiles in humans with Type II diabetes.(47, 54) America's growing love of olive oil is one of its few healthy widespread dietary habits. (And for the record, concern over the conversion of [cis] oleic acid to [trans] elaidic acid during cooking is often overblown. Although it's best to avoid excessively long, high-temperature heating like deep frying, it's really the commercial hydrogenation process that's problematic.)
Linolenic acid, generally consumed in supplement form via flax seeds/ oil, is our other "common" pharmaceutical-looking lipid. For starters, it's more readily oxidized than linoleic acid (the common omega-6 type).(18) That's pretty interesting in itself. A high-calorie fuel source that's less likely to join your love handles could well be used to fuel energy-costly protein synthesis (e.g. muscle growth). And like garlic, phytochemicals associated with the oil (in this case flax lignans) may be additionally helpful.
Lignans are bioavailable and inhibit estrogenic effects.(23, 36) High-lignan flax oil is, in fact, commonly used to combat gynocomastia ("bitch tits") among bodybuilders, as is done pharmaceutically via the anti-aromatases, Arimidex and Teslac. If you're one of the majority of the population that gets too little omega-3s for optimal physiologic effects (52), flax oil may be a nice addition to your diet.
Okay, so we've seen a ton of information on beneficial fatty acids but what about sticking them on a glycerol backbone to make a complete fat molecule? Triglycerides (or "tri-acyl-glycerols"), as you may recall from Part One, are the way we consume the vast majority of dietary fat. Often, though, we're getting three of the same common fatty acids partnering-up. Clever researchers, however, have long been creatively synthesizing structured triglycerides, incorporating any three special fatty acids onto a given glycerol molecule. This is rather cool because it enhances the absorption of the fatty acid stuck in the middle (the "2-position")(6).
Sticking a readily oxidized medium chain fatty acid in the one- or three-position, appears to help, creating a sort of martyr-like "hug the grenade and save your buddy" effect. Results in human trials indicate anti-catabolism and generally improved effects compared to simple physical mixtures.(2, 6, 8, 53) And these data are supported by plenty of rat research on the topic that I won't attempt to list here. Unfortunately for bodybuilders, esterifying such structured lipids has historically been prohibitively expensive. Fortunately, this is changing as technology progresses.
Are you starting to get the idea that special fats are potent and helpful? Let me offer just a few more tidbits – this time applied to athletic performance. First, early studies on fats' inferiority to carbohydrates for performance may have been due to insufficient adaptation periods prior to the exercise. It shouldn't be any surprise that putting extra fat in a carb-adjusted person is like dumping diesel fuel into a gasoline engine. Is there any wonder that performance suffered?
Second, selecting beneficial fats over more common ones could help reduce exercise-based oxidative stress. Cannon and colleagues incriminated soybean oil as a pro-oxidant (which has a little linolenic acid, but not much) after examining muscle damage from exercise.(16) This is in stark contrast to what we've seen regarding olive oil. When taken in the context of other published work, this further suggests that reducing "common" oils, perhaps while supplementing vitamin E, is prudent for athletes.
Okay, my final point regarding exercise-fat interactions regards cytokines. A theme you may see in my writings is the manipulation of immune function via nutrients ("immunonutrition"). It plays a huge role in muscle recovery. Having said that, researchers have documented that athletes can decrease the pro-inflammatory / catabolic interleukin-6 in a stepwise manner with progressively higher fat intakes.(55). Cool.
Let's conclude with a note on practicalities. As I mentioned, fats don't offer immediate gratification. Starting a healthier fat regime won't put 30 pounds on your bench press, bloat you up 5 pounds overnight or wire you like Ben Franklin in a storm just 30 minutes before a workout. For the same metabolic reasons, lipid supplementation must be done cautiously. Unlike creatine, for example, fats won't simply fill up your muscles like a balloon... they will become the balloon. Fats, more than most other nutrients, exemplify the idiom "you are what you eat". Incorporation into (muscle, fat) cell membranes isn't something you eliminate immediately if you don't like the effects. Washout periods for fish oils have been reported as 10-18 weeks.(20, 27) Wow. This isn't necessarily a bad thing, however, as a month's intake will last long after an intervention period ("cycle"), saving tons of money compared to other supplements.
We've just begun to explore the tip of the iceberg regarding dietary fats and the inappropriateness of their demonization. Clearly there are benefits to be had by altering one's fat choices. I've done my best (judging by the onerous size of this freaking dissertation) to offer interesting facts and creative potential applications for all sorts of dietary fats and oils. Take it all with a grain of salt, though, and don't ignore the omnipresent negative data regarding lipids either.
Animal and in vitro data are just one supportive brick in the edifice. Although many are included here, more human studies are coming out all the time. My hope is that athletes in particular will benefit from seeing the big picture – not the media version – which includes the seldom-revealed "other half" of the research. It's undeniably out there. Whether you prefer an indiscriminately high fat diet or still choose low-fat food items like I do (I still avoid the kind of fat present in most "fun foods"), hopefully now you're better informed.
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