n-3 Fatty acid fortification: opportunities and obstacles.

There is a growing recognition that low tissue levels of long-chain n-3 fatty acids (LC n-3 FA; EPA and DHA) are associated with increased risk for coronary heart disease (CHD) (Wang et al. 2006), and perhaps neuropsychological diseases (Hibbeln et al. 2006). The most direct approach to correcting this deficiency is, of course, to increase the dietary intake of foods rich in these FA, which typically means fish and shellfish. Indeed, the American Heart Association has recommended that adults without known CHD consume at least two preferably oily fish meals per week to reduce their risk for cardiac events (Kris-Etherton et al. 2002). Similar recommendations have been made by health authorities in the United Kingdom (Scientific Advisory Committee on Nutrition/Committee on Toxicology, 2004) and Australia (National Health & Medical Research Council, 2006). However, it is not clear whether the world’s oceans could meet this demand. According to a recent report, we are witnessing an ever accelerating loss of ocean biodiversity which could lead to ‘the global collapse of all taxa currently fished by the mid-21st century’(Worm et al. 2006). Whether this dire prediction will prove to be true or not, the strategy of providing n-3 FA via ‘a fish in every pot’ may not be realistic. However at present, there are few substitutes for the LC n3 FA in seafood. So where can we turn in order to obtain these FA? There are several options, including increased production of oil-rich but inedible fish species (e.g. menhaden), the use of single-celled organisms to biosynthesize EPA and DHA (Meyer et al. 2004), and the use of biotechnology to produce both plants (Ursin, 2003) and animals (Lai et al. 2006) enriched in LC n-3 FA. Each of these approaches will play a part in meeting the growing demand for EPA and DHA. But how will these FAactually reach the consumer if not in a fishfillet? It is here that the report by Murphy et al. (2007) in this issue of the British Journal of Nutrition provides uswith a glimpse of the future: fortification of ‘regular’ foods with (tasteless! ) LC n-3 FA. Based on the unquestioned success of fortification programmes with iodine, folic acid, vitamin D and B-vitamins, the surreptitious inclusion of these FA into the food supply is the best approach for raising LC n-3 FA levels in the entire population. By using a wide variety of ‘lightly’ fortified foods (generally providing between 50 and 150mg EPA þ DHA per serving of cheese spread, chocolate, instant oats, milk, dips, biscuits, pancakes, muffins, breads, salad dressings, margarines, dry soup mixes, cereals, and eggs), these investigators were able to increase the daily LC n-3 FA intake from one typical of the Australian diet (100–200mg/d) to 1000mg/d. This is the intake recommended by the American Heart Association for patients with known CHD (Kris-Etherton et al. 2002). Over the 6-month study, erythrocyte levels of EPA and DHA (expressed as a % of total FA; the omega-3 index (Harris & von Schacky, 2004)) rose from about 4% to over 7%. Even at 6 months when steady state levels may still not have been reached, this level is quite close to the proposed target of 8% associated with significantly reduced risk for death from CHD (Harris & von Schacky, 2004). For the most part, the fortified foods were well-received and could not be distinguished from their unfortified counterparts. Therefore, in confirmation of a previous study (Lovegrove et al. 1997), Murphy et al. demonstrate that heart-healthy tissue levels of LC n-3 FA may be achieved solely with fortified foods, without any fish or fish oil capsules. Although the list of foods currently fortified with LC n-3 FA is growing (Whelan & Rust, 2006), why is it still so short? Why has the food industry been slow to respond? What are the obstacles preventing companies from rushing headlong into LC n-3 FA fortification? It is not the lack of high quality, deodorized and stabilized oils enriched with LC n-3 FA since these are currently available, and more will be produced as demand grows. What is lacking is the demand. Why? At least partly because of the inability of food manufacturers to make clear, direct and strong health claims for their products. Without a way to inform consumers that a product fortified with EPA and DHA provides a health benefit that more than justifies the slightly increased cost over the non-fortified product, the industry lacks the incentive to produce such foods.