Health Benefits of Omega-3 Fatty Acid Supplementation

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Current State of Science Review focusing on efficacy, safety and varioususes for oral Omega-3 Fatty Acids


By Amy Fitzpatrick, MS, RD
Corporate Nutritionist & Research Consultant, Natural Health Solutions, Kingsport, TN 37665
Nutrition & Natural Products Research & Education

Summary

Research suggests that increasing your intake of omega-3 fatty acids may help you maintain optimal health, including cardiovascular health,1,2 joint health,3,4 mood/cognitive health5,6 and bone health.7 Omega-3 fatty acids include alpha linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These fatty acids are essential for life because they serve as chemical building blocks for your body?s production of prostaglandins?biologically active compounds that are involved in a host of functions from blood vessel dilation to hormone balance, among others.8,9,10 Both government and public health organizations recognize the importance of omega-3 fatty acids and support the need for improved intakes among the population.11,12,13 Research suggests that the typical American diet may fall short of an adequate intake of omega-3 fatty acids for optimal health;14,15 therefore, omega-3 fatty acid supplementation is a convenient way to improve your daily intake of these essential fats while supporting a variety of body systems.


Background



Omega-3s: The Key to Good Health?
The discovery of the benefits of omega-3 fatty acids dates back to the early 1970s when scientists were studying the Inuit (Eskimo) people of Greenland. As a group, the Inuit suffered far less from cardiovascular disease than their European counterparts despite their very high fat diet
from eating whale, seal and salmon.16 Eventually researchers realized that the common denominator in these foods were the high content of omega-3 fatty acids, which later proved to provide numerous protective health benefits.


Thousands of research studies have been undertaken to better understand the role omega-3 fatty acids play in health and disease prevention. As early as 1929, scientists discovered that certain fats were essential for life. They found that animals deprived of these fats (later pinpointed as essential fatty acids) developed growth retardation, skin lesions, impaired fertility and many other problems that would eventually lead to death.17 Scientists wouldn?t know until many years later that the same fats that protected the Inuits from disease (ie, omega-3 fatty acids) would also be
essential in controlling the balance of virtually every system in the body.


The ABCs of EFAs
Omega-3 fatty acids are a part of a team of essential fatty acids (EFAs); these fats are ?essential? because they are not manufactured by the human body, and must, therefore, be obtained through the diet. Alpha-linolenic acid (ALA), an omega-3 fatty acid, and linoleic acid (LA), an omega-6 fatty acid, are the predominant essential fatty acids that must be consumed in the diet for good health. ALA is the precursor or ?parent? to two other important omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); in other words, ALA is converted in the body to EPA and DHA. Important plant sources of ALA include walnuts, flaxseed, flaxseed oil, canola oil and soybean oil. EPA and DHA are found predominantly in fatty fish and fish oil and are the omega-3 fatty acids that were responsible for protecting the Inuit people. LA is found in vegetable oils such as corn, safflower, cottonseed, sesame and sunflower seed oils.


What?s The Big Fat Deal?
In this day and age of fat phobia and the enormous amount of low-fat and nonfat food products that appear on grocery shelves, supplementation with fats may seem puzzling. Interestingly, the understanding of how fats truly affect our health has only recently been uncovered by researchers. Throughout the years, the ?fat is bad? message has been pervasive in our society. Yet even though low-fat, no-fat diets have been promoted for years, rates of obesity, diabetes, heart disease and cancer have skyrocketed. Scientists now know that the ratio and type of fat in the diet is the most important predictor of good health and disease prevention.


It?s true that certain fats can be harmful when eaten in excess (ie, saturated fat and hydrogenated or trans fatty acids); however, the omega-3 and omega-6 fatty acids are essential for a multitude of physiological functions and individuals should make sure these fats are present in the diet in appropriate amounts.


For instance, reports indicate that current diets in the United States are too low in omega-3 fatty acids, compared to the relatively high intakes of saturated fats, trans fats and omega-6 fatty acids.18 While saturated and trans fat intake should be minimized, omega-6 fatty acids should continue as a dietary mainstay, but balanced with adequate omega-3 fatty acid intake. Dietary intake studies indicate that the ratio of omega-6 to omega-3 fatty acids may be too high for
optimal health.18 Researchers estimate that the ratio of omega-6 to omega-3 fatty acids is still much higher (eg, 10-30:1) than that recommended by some health care professionals (ie, 2- 3:1).14,19 In other words, the omega-6 content of the diet should be only 2-3 times higher than the omega-3 content.


What?s the problem with this offset ratio? An adequate balance of the omega-3 fatty acids ALA, EPA and DHA with the omega-6 fatty acid, linoleic acid, is essential to ensure that many processes are functioning appropriately, including, blood pressure, blood clotting, lipid levels,
blood vessel function, immunity and more. High intakes of saturated fats, trans fats and linoleic acid and low intakes of omega-3 fatty acids also create an inflammatory environment, which is now regarded as fundamental in the development of a number of diseases.20


To keep this ratio optimal, foods rich in omega-3 fatty acids should be used to replace foods high in saturated fats such as red meat, processed meats, whole milk and pastries. Flaxseeds, flaxseed oil, walnuts, purslane (a leafy vegetable), fish and fish oil are all good sources of omega-3 fatty acids and should be consumed on a regular basis. Moderate consumption of foods made with linoleic acid rich vegetable oils such as corn, safflower,
cottonseed and sunflower seed oils and the use of heart healthy olive oil as the main cooking oil should be considered. Finally, intake of trans fatty acids from processed foods such as baked goods, coffee creamers and snack foods should be eliminated or kept to a minimum.


Cardiovascular Health
Most of the research on the health benefits of the omega-3 fatty acids has centered on their role in reducing the risk of cardiovascular disease. From population studies to cell culture and animal studies to randomized controlled trials, the cardio-protective effects of omega-3 fatty acids are
now well recognized.21 The totality of the scientific evidence to date has convinced the American Heart Association/American College of Cardiology22 , the European Society for Cardiology23, the Agency for Healthcare Research and Quality at the National Institutes of Health 24, the Harvard Center for Risk Analysis25 , and several international bodies13,26,27,28 to conclude that omega-3 fatty acids from fish and fish oil play a role in reducing the risk of cardiovascular disease, the number one killer of both men and women in the United States.


Although the majority of research has attributed the cardiovascular benefits of omega-3 fatty acids to fish and fish oil sources (ie, EPA and DHA), preliminary research does suggest that plant sources of the omega-3 fatty acid ALA may have cardio-protective properties.1,29,30,31,32 However,
until further well-controlled trials emerge to confirm the specific benefits of ALA for cardiovascular health, fish and fish oil should be the primary source of omega-3 fatty acids for cardiovascular benefits.33


Fish oil has been primarily shown to lower triglyceride levels, and in some cases, increase HDL cholesterol or ?good? cholesterol levels.34,35,36 However, the preventive nature of omega-3 fatty acids in regards to cardiovascular disease may not be solely attributed to the beneficial effects observed on lipid levels. Omega-3 fatty acids may also have mild anti-thrombotic (blood clot reducing) and blood pressure lowering properties as well as positive effects on arterial function (improved dilation and elasticity), 37 stabilization of atherosclerotic plaques38 and reductions in arrhythmias.33

There is considerable evidence for a protective effect of omega-3 fatty acids from fish and fish oil in reducing the risk of heart disease and/or its complications.2,39,40,41,42 For instance, one of the largest studies to date found that omega-3 fish oil significantly reduced the rate of death, non-fatal heart attack and stroke in individuals who had previously suffered a heart attack.41 Other findings suggest that omega-3 fatty acids from fish oil may also improve exercise capacity in patients with coronary artery disease, and possibly heart rate variability, particularly in patients with recent heart attacks.36

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While these findings are all important, it should be noted that many questions remain unanswered. Although fish oil has shown significant cardiovascular benefits in many studies, it is not known if fish oil supplementation is equivalent to the benefits of regular fish consumption in reducing the risk of certain cardiovascular outcomes; nor have controlled trials shown prevention of cardiovascular disease with long term fish oil consumption in healthy populations. While most
regulatory bodies have encouraged the need for increased intakes of omega-3 fatty acids to help reduce the risk of cardiovascular disease, their recommendations have centered on increasing the consumption of omega-3 rich fish and plant sources of omega-3 fatty acids with supplements as the secondary choice when dietary intake is inadequate. However, in terms of dietary supplementation with omega-3 fatty acids, in their evaluation of a cardiovascular health claim for dietary supplements containing omega-3 fatty acids from fish oil, the American Food & Drug
Administration has cautiously endorsed omega-3s.11 In November 2000, they completed a review that found that "the scientific evidence that omega-3s may reduce the risk of heart disease is suggestive". Although they tempered their statement with the disclaimer that the data is "not conclusive" and that further studies are needed, it is truly a milestone for omega-3 fatty acids.

Joint Health
More than a dozen clinical studies have consistently demonstrated positive benefits in relieving morning stiffness and joint tenderness with fish oil supplementation.4,43,44 Randomized clinical trials indicate that omega-3 fatty acids are superior to placebo (ie, inactive treatment) in improving a variety of outcome measures, and, in some cases, can decrease the long-term requirements for
nonsteroidal anti-inflammatory drugs.45,44

Clinical research in humans has found that these improvements have also been associated with significant decreases in levels of interleukin (IL)-1 beta (a proinflammatory compound).46 Furthermore, preliminary experimental research suggest that the incorporation of omega-3 fatty acids (but not other polyunsaturated or saturated fatty acids) into joint cartilage cells results in a reduction in: (i) the expression and activity of cartilage degrading enzymes and (ii) the expression of inflammatory biomarkers (eg, interleukin (IL)-1alpha, tumor necrosis factor (TNF)-alpha) and cyclooxygenase (COX-2)).47,48 These findings provide preliminary evidence that omega-3 fatty acid supplementation may affect specific regulatory mechanisms involved in the cause and propagation of joint health complications.

Although these studies are promising, additional clinical trials are warranted to determine if these findings extend to a variety of individuals that suffer joint discomfort from various causes. Furthermore, the size of the effect reported in clinical trials to date appears modest at best and
may take up to 12 weeks to notice any benefit.46 Further research is necessary to determine the optimal dosage and any confounding lifestyle factors to conclusively prove that omega-3 fats have a true impact on preserving joint health.

Cognitive Health
Researchers have known for years that omega-3 fatty acids are essential for normal brain development and function and must be provided by the diet. It is well known that maternal levels of omega-3 fatty acids during pregnancy determine the levels present in the infant, and the omega-3 fat, DHA is particularly critical in supporting infant growth, brain development and visual function.49

Interestingly, studies have linked supplementation with DHA by breastfeeding mothers to improvements in cognitive and psychomotor skills during childhood.50,51 Although more research is needed to determine the benefits that DHA supplementation may offer to breastfed children, many women don?t consume DHA rich foods, such as fish; therefore, a DHA supplement is an easy way to increase their daily intake. Experts on lipid nutrition recommend lactating women
consume 300 mg of DHA per day,52which is over four times the typical intake for women living in the United States.53

More recently, studies suggest that supplementation with omega-3 fatty acids by children and adults may also support cognitive function and mood.5,654,55,56,57,58 Preliminary research, which has reported significant improvements in reading, spelling, and behavior in some children taking fish oil supplements6 has spurred additional research studies to further clarify the association

between omega-3 fatty acids and brain function. While some researchers have reported an association between omega-3 fatty acids, cortical processing and improved cognitive function in adults;58 other researchers have noted contradictory results.57 Currently, there is insufficient research to conclusively determine whether omega-3 fatty acid supplementation can improve cognitive skills in mature adult brains and/or protect against cognitive decline.57,59

The association between omega-3 fatty acids and mood was discovered when researchers found that greater seafood consumption was associated with lower prevalence rates of major depression across several different countries.60 Follow-up studies have continued to document this association and have also found deficits in omega-3 fatty acids in people with depressive disorders,61 while several treatment studies indicate therapeutic benefits from omega-3 fatty acid supplementation.62 Improvements in mood have been reported in children63 and adults5,64,65,66 taking fish oil supplements.

Although more clinical research is necessary to better understand the potential benefit of omega- 3 fatty acid supplementation for improved brain health, the findings thus far are intriguing.

Weight Management
Although fish eating populations (eg, Mediterranean, Pacific Islanders, Asians, etc.) have often been noted to have low rates of obesity, it wasn?t until the last few years that the relationship between omega-3 rich fish oil and weight management was documented by experimental and
clinical research. Results from several animal studies suggest that fish oil may decrease body fat stores,67,68,69,70 while some human research suggest a role for fish oil in improving fat metabolism.71,72 For instance, one study found that fish oil reduced body fat mass in healthy adults, and another study found that taking fish oil for 3 to 5 weeks caused a significant increase in fat burning while exercising.

Some researchers have found that omega-3 supplementation in animals may help reduce accumulation of body fat by promoting fat burning and reducing the number of cells in adipose tissue.73 In the study, fish oil fed to mice reduced weight gain induced by a high-fat diet. The researchers noted that the accumulation of adipose tissue?particularly in the abdominal region? was reduced in the animals. The authors also noted that they believe the omega-3 fatty acids, EPA and DHA, increased the burning of fat by activating genes that break down fat in the
mitochondria, or energy producing machines of the body. This in turn, seems to promote weight loss as well as prevent weight gain even when animals were given free access to food.

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The research related to the effects of omega-3 fatty acids, fat metabolism and weight loss is preliminary; therefore, definitive conclusions about their benefit for these purposes cannot be determined at this time. Additional research studies in humans are necessary to better understand the potential for omega-3 fatty acids to promote weight management.

Bone Health
One largely unknown function of omega-3 fatty acids is their important role in skeletal biology and bone health. Bone is a dynamic piece of tissue because it is constantly remodeled and continually undergoes both new formation and resorption (ie, loss of substance). Studies have shown that
omega-3 fatty acids can influence both bone formation and bone resorption in animals.74 For instance, omega-3 rich fish oil appears to reduce the activity of cells that break down bone while lowering bone resorption when fed to rats.75 Also, an EPA enriched diet can also prevent the loss of bone weight and strength in rats caused by estrogen deficiency following ovary removal.76 This
latter finding provides some evidence that omega-3 fatty acid intake may be especially important for bone health in women with low levels of estrogen (eg, menopause, hysterectomy, or ovarectomy), a hormone that is important for bone maintenance.

Recent evidence from the University of California, San Diego, provides further evidence for an association between bone mineral density and the dietary intake of the essential omega-6 and omega-3 fatty acids. When studying more than 1,500 men and women over a four-year period,
they found a higher ratio of omega-6s to omega-3s was associated with lower bone mineral density at the hip. 77 The researchers concluded a more balanced intake of omega-6s to omega- 3s could preserve skeletal integrity in older age. These findings are confirmed by animal studies that show when diets high in omega?6 fatty acids are modified to have a lower ratio of omega?6 to omega?3 dietary fatty acids, bone mass is enhanced.78 Furthermore, dietary supplementation with fish oil, flaxseeds, and flaxseed oil in animals and healthy humans has been shown to
reduce bone resorbing cytokines while simultaneously increasing calcium absorption, bone calcium and bone density.79

The interaction between omega-3 fats and bone health deserves further investigation since it may offer a novel approach to the prevention of osteoporosis, particularly in high risk populations such as menopausal women.

Dosage & Administration
There is currently no recommended dietary intake for the omega-3 fatty acids, ALA, DHA and EPA; however, the National Academies Institute of Medicine (Food & Nutrition Board) have set an adequate intake for ALA at 1.1 gram per day for women, 1.6 gram per day for men, and 1.4 grams per day for pregnancy.53 An adequate intake for EPA and DHA has not been set at this time.

In the United States, the intake of omega-3 fatty acids is ~1.6 g/d, of which 1.4 g is alpha-linolenic acid (ALA) and 100-200 mg is EPA and DHA.14 Although ALA is converted by the body to EPA and DHA, this conversion is modest and controversial.80,81 For example, Emken et al82 reported a 15% conversion, whereas Pawlosky et al83 found only 0.2%; both reported that the conversion to DHA was much less than that to EPA. Therefore, fish and fish oil are the most reliable way to ensure an adequate daily intake of EPA and DHA.

Experts in lipid nutrition have made public health recommendations for the omega-3 fatty acids, EPA and DHA.13,52 They have recommended a minimum of 500 mg of DHA and EPA combined daily, with an ideal daily intake of 650 mg of the two omega-3 fatty acids combined. During pregnancy and lactation women must ensure a DHA intake of 300 mg/d. For individuals with cardiovascular concerns, benefits have been noted in clinical studies at the following dosage range: 900 mg-2.6 grams per day of EPA and DHA combined. Additional clinical studies are needed to determine the optimal dosage for omega-3 fatty acids in terms of joint, cognitive and bone health and weight management.

Safety
Omega-3 rich fish oils have achieved Generally Recognized As Safe (GRAS) status in the United States. Large amounts of fish oil have been consumed with no apparent adverse effects, other than mild gastrointestinal upset. Although the research is contradictory in terms of fish oil increasing the risk of bleeding when combined with blood thinning or anti-platelet medications, individuals taking aspirin, Plavix, Ticlid, Coumadin and others should have their bleeding time monitored when taking several grams of fish oil daily. Furthermore, fish oil can mildly lower blood pressure and might have additive effects in individuals treated with antihypertensive medication.84

Conclusions
While there is an abundance of research on the health promoting benefits of omega-3 fatty acids, it should be recalled that these substances are essential nutrients critical to life itself and many important physiological functions. Unfortunately, the usual dietary intake of omega-3 fatty acids
(EPA, DHA) in the United States is only about 150 mg per day?far less than the amount suggested for optimal health benefits (ie, min. 650 mg to several grams daily). Given the recommendations from a variety of researchers and health care organizations to increase the omega-3 content of the diet, adding more fish and fish oil to the diet on a regular basis seems prudent.

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69. Parrish CC, Pathy DA, Parkes JG, Angel A. Dietary fish oils modify adipocyte structure and function. J Cell Phys.1991;148:493-502.

70. Ballie RA, Takada R, Nakamura M, Clarke SD. Coordinate induction of peroxisomal acyl-CoA oxidase and UCP-3 by dietary fish oil: a mechanism for decreased body fat deposition. Prostaglandin Leukot Essen Fatty Acids.1999;60:351-356.

71. Couet C, Delarue J, Ritz P, et al. Effect of dietary fish oil on body fat mass and basal fat oxidation in healthy adults. Int J Obes.1997;21:637- 643.

72. Huffman DM. Chronic supplementation with fish oil increases fat oxidation during exercise in young men. JEP Online. 2004;7:48-56. Available at: http://www.asep.org/jeponline/issue/.../HuffmanV2.pdf

73. Ruzickova R, Rossmeis M, Prazak T. Omega-3 PUFA of marine origin limit diet-induced obesity in mice by reducing cellularity of adipose tissue. Lipids. 2004; 39:1177-1185.

74. Watkins BA, Li Y, Seifert MF. Nutraceutical fatty acids as biochemical and molecular modulators of skeletal biology. J Am Coll Nutr. 2001;20:410S-416S; discussion 417S-420S.

75. Watkins BA, Li Y, Lippman HE, et al. Omega-3 polyunsaturated fatty acids and skeletal health. Exp Biol Med (Maywood). 2001;226:485-497.

76. Sakaguchi K, Morita I, Murota S: Eicosapentaenoic acid inhibits bone loss due to ovariectomy in rats. Prostaglandins Leukot Essent Fatty Acids. 1994;50: 81?84.

77. Weiss LA, Barrett-Connor E, von M?hlen D. Ratio of n?6 to n?3 fatty acids and bone mineral density in older adults: the Rancho Bernardo Study. Am J Clin Nutr. 2005; 81:934-938.

78. Blanaru JL, Kohut JR, Fitzpatrick-Wong SC, Weiler HA. Dose response of bone mass to dietary arachidonic acid in piglets fed cow milk? based formula. Am J Clin Nutr. 2004;79:139?147.

79. Kettler DB. Can manipulation of the ratios of essential fatty acids slow the rapid rate of postmenopausal bone loss? Altern Med Rev.2001;6:61-77.

80. Gerster H. Can adults adequately convert -linolenic acid (18:3n-3) to eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3)? Int J Vitam Nutr Res.1998;68:159?173.

81. Burdge GC, Jones AE, Wootton SA. Eicosapentaenoic and docosapentaenoic acids are the principal products of -linolenic acid metabolism in young men. Br J Nutr.2002;88:355?363.

82. Emken EA, Adlof RO, Gulley RM. Dietary linoleic acid influences desaturation and acylation of deuterium-labeled linoleic and linolenic acids in young adult males. Biochim Biophys Acta. 1994; 1213: 277?288.

83. Pawlosky RJ, Hibbeln JR, Novotny JA, et al. Physiological compartmental analysis of alpha-linolenic acid metabolism in adult humans. J Lipid Res. 2001; 42: 1257?1265.

84. Natural Medicines Comprehensive Database. Fish Oil Monograph. Available at: www.naturaldatabase.com Accessed on July 10, 2006.

[DRP7]

thanks for sharing this great article, Vanessa! It is an excellent summary and source for further research articles / references for all who wnat to dig a little deeper into this topic.
too bad I must spread some reps before I can rep you again. But I won't forget!

[in10city]

I wonder if either of you could comment on this...

I was discussing the comsumption of fats post-training and someone opined that it would be a good time to consume Omega-3's to help combat inflammation, to assist in fat loss, etc ... then I said, maybe not - since Omega-3's influence prostaglandin production (PGF2a) which in turn is related to protein synthesis, would or could this lead to less of an impetus for protein synthesis post-training?

And we sort of left it open-ended there ... It might seem like splitting hairs but everything I've read points to that conclusion ... Any thoughts on this?

[NO HYPE]

Edit

[in10city]

Thanks... The paragraph above it is actually more to the point ...

Dietary fatty acids significantly effects prostaglandin production. Diets high in omega-3 fatty acids (fish oil, flax oil) decrease prostaglandin production. Diets high in omega-6 fatty acids (corn oil) increase prostaglandin production. Once again you have pros and cons with trying to manipulate PGF2a production with your diet. By increasing omega-3s, you get lower levels of PGF2a and probably a less intense stimulus of protein synthesis immediately after you workout. On the other hand by increasing omega-3s you reduce inflamation, pain, increase GLUT4 content, and a whole host of other factors related to cardiac risk. I don?t think its as clear cut as Dr. Sears (Zone Diet) would have you believe. Trying to manipulate the diet to control prostaglandin kinetics is fraught with complexity making black and white statements difficult to support.

[deserusan]

Originally Posted by Amy Fitzpatrick, MS, RD

They have recommended a minimum of 500 mg of DHA and EPA combined daily, with an ideal daily intake of 650 mg of the two omega-3 fatty acids combined.

13. International Society for the Study of Fatty Acids and Lipids (ISSFAL). Recommendations for intake of polyunsaturated fatty acids in healthy adults. Available at: http://www.issfal.org.uk/Welcome/PolicyStatement3.asp. Accessed July 8, 2006.

52. Simopoulos AP, Leaf A, Salem N Jr. Workshop on the essentiality of and recommended dietary intakes for omega-6 and omega-3 fatty acids. J Am Coll Nutr. 1999;18:487-489.

I'm glad this has come up. Too many people are getting in way too much EPA/DHA which is actually detrimental to hypertrophy. While too much inflammation is not ideal nor is too little. Those guys taking in their 10-20 fishoil caps a day are actually limiting their gains because of excessive DHA/EPA content.

Originally Posted by in10city

I wonder if either of you could comment on this...

I was discussing the comsumption of fats post-training and someone opined that it would be a good time to consume Omega-3's to help combat inflammation, to assist in fat loss, etc ... then I said, maybe not - since Omega-3's influence prostaglandin production (PGF2a) which in turn is related to protein synthesis, would or could this lead to less of an impetus for protein synthesis post-training?

And we sort of left it open-ended there ... It might seem like splitting hairs but everything I've read points to that conclusion ... Any thoughts on this?

I think this would heavily be contingent on what the actual fat source is. I'm eating about an ounce of almonds PWO with eggwhites. The O3 content in almonds is primarily ALA which as mentioned will have a poor conversion and thus not effect inflammation because of digestion primarily of the fibrous nature of almonds. When it does get converted and in circulation I'm sure the inflammation response to eccentric motion would have subsided already so the effect would be limited greatly if it even existed.

On the other hand, if I was drinking fish oil PWO it would effect the inflammation response greatly. As mentioned before, the inflammation response is necessary for muscle growth and immune response:

As described earlier, resistance exercise causes trauma to skeletal muscle. The immune system responds with a complex sequence of immune reactions leading to inflammation (3). The purpose of the inflammation response is to contain the damage, repair the damage, and clean up the injured area of waste products.

The immune system causes a sequence of events in response to the injury of the skeletal muscle. Macrophages, which are involved in phagocytosis (a process by which certain cells engulf and destroy microorganisms and cellular debris) of the damaged cells, move to the injury site and secrete cytokines, growth factors and other substances. Cytokines are proteins which serve as the directors of the immune system. They are responsible for cell-to-cell communication. Cytokines stimulate the arrival of lymphocytes, neutrophils, monocytes, and other healer cells to the injury site to repair the injured tissue (4).

The three important cytokines relevant to exercise are Interleukin-1 (IL-1), Interleukin-6 (IL-6), and tumor necrosis factor (TNF). These cytokines produce most of the inflammatory response, which is the reason they are called the “inflammatory or proinflammatory cytokines” (5). They are responsible for protein breakdown, removal of damaged muscle cells, and an increased production of prostaglandins (hormone-like substances that help to control the inflammation).

http://www.unm.edu/~lkravitz/Article...pertrophy.html

4. Pedersen, B. K. Exercise Immunology. New York: Chapman and Hall; Austin: R. G. Landes, 1997.

5. Pedersen, B. K. and L Hoffman-Goetz. Exercise and the immune system: Regulation, Integration, and Adaptation. Physiology Review 80: 1055-1081, 2000.

[Mr.Farang]

Originally Posted by deserusan

I'm glad this has come up. Too many people are getting in way too much EPA/DHA which is actually detrimental to hypertrophy. While too much inflammation is not ideal nor is too little. Those guys taking in their 10-20 fishoil caps a day are actually limiting their gains because of excessive DHA/EPA content.
:

10 ~ 20 fishoil caps??!?!?!?!?! geeeez!

Originally Posted by deserusan

I think this would heavily be contingent on what the actual fat source is. I'm eating about an ounce of almonds PWO with eggwhites. The O3 content in almonds is primarily ALA which as mentioned will have a poor conversion and thus not effect inflammation because of digestion primarily of the fibrous nature of almonds. When it does get converted and in circulation I'm sure the inflammation response to eccentric motion would have subsided already so the effect would be limited greatly if it even existed.

On the other hand, if I was drinking fish oil PWO it would effect the inflammation response greatly. As mentioned before, the inflammation response is necessary for muscle growth and immune response:

that's great info!!!!!! thank you!

[NO HYPE]

Originally Posted by in10city

I wonder if either of you could comment on this...

I was discussing the comsumption of fats post-training and someone opined that it would be a good time to consume Omega-3's to help combat inflammation, to assist in fat loss, etc ... then I said, maybe not - since Omega-3's influence prostaglandin production (PGF2a) which in turn is related to protein synthesis, would or could this lead to less of an impetus for protein synthesis post-training?

And we sort of left it open-ended there ... It might seem like splitting hairs but everything I've read points to that conclusion ... Any thoughts on this?

If anyone finds some good info on this matter.... please feel free to comment in the link provided below.

Antioxidants... Do they hinder our gains or not?

[Deraj]

It's tough designing and maintaining a diet that increases lean mass, reduces fat's and is completely healthy. It really depends ultimately on a persons goals and genetics. I'm on a bulking cycle now and my diet gives me close to 500 mg of cholesterol a day, not good concidering atherosclerosis runs in the family. I supplement with EPA/DHA to reduce imflammation which has been identified as a leading cause of that and coronary artery disease noted here in the New England Journal of Medicine; http://content.nejm.org/cgi/content/extract/352/16/1685
I did however discover recently that you can track and indentify your daily diets total "inflammation factor" by researching the foods inflammation qualities listed at http://www.nutritiondata.com/
After some reading and calculation I found my diet to be extremely inflammatory, not good. I'm only 31 so I still have time. By using the EPA/DHA supplements (with no vitamin a or k) I was able to get my daily inflammation down to zero. I'm not a doctor or a scientist but it would seem to me that light supplementation of DHA/EPA is good for everyone but heavier supplementation is a must for people with inflammation related conditions also noted in this article by the Counsel for Responsible Nutrition;
http://www.crnusa.org/benpdfs/CRN010benefits_omega3.pdf
Yes Omega-3's will affect PGF2a but it's important for each individual to determine what's most important to their specific genetic needs. I want to bulk, but I'm willing to slow it a bit to ensure long term cardiac health. Have a fasting lipids test, VGA Cholesterol test and a test for C-reactive proteins. All will tell if a persons at risk for atherosclerosis, then the appropriate dietary modifications and supplement decisions can be made.