Higher omega-3 intake builds bone density from ages 16 to 22; omega-6 rivals tend to tear it down

by Craig Weatherby

Some novel findings in young men add to the evidence that higher omega-3 intake helps build stronger bones.

And they reinforce the idea that bone health also improves when people limit intake of omega-6 fatty acids, which predominate in most cooking oils, dressings, meats, poultry, and packaged, prepared, or fast foods (see “Omega-3s Seen as Stellar Bone-Builders”).

Researchers at Sweden's Umeå University report that young men with higher blood levels of omega-3s have denser, stronger bones (Hogstrom M et al 2007).

Surprisingly, no one had ever examined the association between body levels of dietary fatty acids and standard markers of bone strength such as bone mineral density or BMD.

In previous studies, researchers relied on food intake questionnaires to estimate people's intake of fatty acids relative to their bone density: a factor associated with bone strength, though not always synonymous with reduced fracture risk.

What the study found

A team led by Magnus Högström, PhD recruited 78 healthy young men (average age of 16.7 years) from high schools and sports clubs, measured total body bone mineral density (BMD), and took blood samples to measure their levels of omega-3 and omega-6 fatty acids.

About eight years later, Dr. Högström's group found that the young men with the highest tissue levels of omega-3s had the best (highest) total-body BMD and spinal BMD, and the greatest growth in BMD between the ages of 16 and 22.

Of the two omega-3sDHA and EPAlevels of DHA had the closest associations with these two measures.

As Chaim Vanek, M.D. and William Connor, M.D. of Oregon Health & Science University said in an accompanying editorial, “The study by Högström et al. nicely adds to a growing body of evidence that n-3 fatty acids are also beneficial to bone health” (Vanek C, Connor WE 2007).

Drs. Vanek and Connor hypothesized that the apparent benefits might relate to the opposite effects of omega-3 and omega-6 fatty acids with regard to cell receptors for a genetic switch called PPAR-gamma, excessive activation of whose cell receptors is associated with lower bone mass:

  • Omega-6 fatty acids, in excess, weaken bone because they activate PPAR-gamma cell receptors in bone marrow. Americans consume far too many omega-6s.

  • Omega-3 fatty acids conserve bone density, because they do not activate PPAR-gamma cell receptors in bone marrow.

Although Drs. Vanek and Connor say that omega-3s do not activate PPAR-gamma cell receptors in bone marrow, diabetes studies indicate that marine omega-3s do activate PPAR-gamma receptors in fatty adipose tissue found under the skin and around internal organs (see Abedin M et al 2006 and other PPAR-omega-3 papers, below).

We haven't been able to confirm or resolve this apparent contradiction, so we welcome any enlightening communications.

Suffice it to say that higher omega-3 intake clearly helps build and conserve bone health, no matter how.

If diets higher in omega-3s than average promote better bone density they could help prevent many fractured bones throughout life, and in later years, help prevent the broken major bones that lead to disablement and many premature death spirals.


  • Hogstrom M, Nordstrom P, Nordstrom A. n-3 Fatty acids are positively associated with peak bone mineral density and bone accrual in healthy men: the NO2 Study. Am J Clin Nutr. 2007 Mar;85(3):803-7.
  • Terano T. Effect of omega 3 polyunsaturated fatty acid ingestion on bone metabolism and osteoporosis. World Rev Nutr Diet 2001;88:141–7.
  • Van Papendorp DH, Coezter H, Kruger MC. Biochemical profile of osteoporotic patients on essential fatty acid supplementation. Nutr Res 1995;15:325–34.
  • Watkins BA, Li Y, Lippman HE, Feng S. Modulatory effect of omega-3 polyunsaturated fatty acids on osteoblast function and bone metabolism. Prostaglandins Leukot Essent Fatty Acids 2003;68:387–98.
  • Weiss LA, Barrett-Connor E, von Muhlen 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;81:934–8.

PPAR-omega-3 papers

  • Abedin M, Lim J, Tang TB, Park D, Demer LL, Tintut Y. N-3 fatty acids inhibit vascular calcification via the p38-mitogen-activated protein kinase and peroxisome proliferator-activated receptor-gamma pathways. Circ Res. 2006 Mar 31;98(6):727-9. Epub 2006 Mar 2.
  • Itoh T, Murota I, Yoshikai K, Yamada S, Yamamoto K. Synthesis of docosahexaenoic acid derivatives designed as novel PPARgamma agonists and antidiabetic agents. Bioorg Med Chem. 2006 Jan 1;14(1):98-108. Epub 2005 Sep 29.
  • Larsen LN, Granlund L, Holmeide AK, Skattebol L, Nebb HI, Bremer J.
  • Li H, Ruan XZ, Powis SH, Fernando R, Mon WY, Wheeler DC, Moorhead JF, Varghese Z. EPA and DHA reduce LPS-induced inflammation responses in HK-2 cells: evidence for a PPAR-gamma-dependent mechanism. Kidney Int. 2005 Mar;67(3):867-74.
  • Rodriguez-Cruz M, Tovar AR, del Prado M, Torres N. [Molecular mechanisms of action and health benefits of polyunsaturated fatty acids] Rev Invest Clin. 2005 May-Jun;57(3):457-72. Review. Spanish.
  • Sulfur-substituted and alpha-methylated fatty acids as peroxisome proliferator-activated receptor activators. Lipids. 2005 Jan;40(1):49-57.
  • Vanek C, Connor WE. Do n-3 fatty acids prevent osteoporosis? Am J Clin Nutr. 2007 Mar;85(3):647-8.
  • Yamamoto K, Itoh T, Abe D, Shimizu M, Kanda T, Koyama T, Nishikawa M, Tamai T, Ooizumi H, Yamada S. Identification of putative metabolites of docosahexaenoic acid as potent PPARgamma agonists and antidiabetic agents. Bioorg Med Chem Lett. 2005 Feb 1;15(3):517-22.
  • Zhao G, Etherton TD, Martin KR, Vanden Heuvel JP, Gillies PJ, West SG, Kris-Etherton PM. Anti-inflammatory effects of polyunsaturated fatty acids in THP-1 cells. Biochem Biophys Res Commun. 2005 Oct 28;336(3):909-17.