Grass-Fed Lamb

When we think about omega­3 fats and their availability from plants versus animals, we usually think about nuts and seeds on the plant side of things and fish on the animal side. But on the animal side of things, we should also think about grass-fed lamb! The omega­3 content of lamb depends upon the young sheep's diet as well as the mother's diet, but when those diets are nutritionally supportive, the result can be a cut of lamb with an impressive amount of omega­3s. In regions of some countries without access to a coastline and fish, lamb has sometimes been shown to provide more omega­3s than any other food in the diet. In Australia, where lamb is eaten frequently by both children and adults, recent studies have shown lamb to rank among the top omega­3 foods in the daily diet. Grass-fed lamb has been shown to average at least 25% more omega­3s than conventionally fed lamb, including as much as 49% more ALA (alpha linolenic acid, the basic building block for omega­3s). In our own nutritional profile of grass-fed lamb, we use a conservative average estimate of 40 milligrams of omega­3s per ounce of roasted lamb loin. That's 50% of the omega­3s in an ounce of baked cod fish or broiled tuna, and 67% of the amount in an ounce of sesame seeds.

Conjugated linoleic acid (CLA) is a health supportive omega­6 fatty acid that has surprised researchers in terms of its health benefits. Since the average U.S. adult consumes too many omega­6 fatty acids in relationship to omega­3s, research studies often fail to show health benefits for increased amounts of individual omega­6 fatty acids. In addition, CLA is not only an omega­6 fatty acid but also a trans fatty acid. As a general rule, it is best to keep your intake of trans fats as low as possible. Yet, CLA appears to be an exception to the rule about omega­6s and trans fat because an ever-increasing number of studies show increased intake of CLA to be associated with improved immune and inflammatory function, improved bone mass, improved blood sugar regulation, reduced body fat, and better maintenance of lean body mass. Recent studies show that grass-fed lamb contains nearly twice as much CLA as conventionally fed lamb. Interestingly, lambs grazing during the spring and summer months store more CLA than lambs grazing during the fall and winter; higher CLA storage is also found for lambs grazing on highland and mountain pastures. Studies have also shown intake of fresh pasture grasses to be associated with significantly more CLA in lamb than feeding of the same
grasses in dried form. In our nutrient profile for grass-fed lamb, we use a very conservative estimate of CLA of 25 milligrams in 4 ounces. We've seen some studies showing two to seven times this amount, depending on the specific feeding and lifestyle circumstances.

Several recent studies show that overall fat levels in lamb can be reduced through the practice of grass feeding. This reduction in overall fat content has also been shown to be particularly apparent in loin cuts of lamb. Even though the average daily weight gain in conventionally fed versus grass-fed lambs has been shown to be similar in these studies, the foraging process has been shown to lower total fat content by a minimum of approximately 15%. This finding makes good sense to us. Lambs out in pasture are more active than lambs kept indoors, and this greater level of activity is likely to have the animals develop more muscle and burn more calories as well. In addition, lambs out in pasture are likely to eat less. Unlike lambs kept indoors and fed concentrate, lambs grazing outdoors are more likely to get involved in other activities and be less focused on feeding regimens.

Because lamb has received much less attention in the research literature than its fellow ruminant meat—namely, beef—we have been unable to find large­scale research studies on humans that analyze lamb intake and its relationship to disease. Another factor involved with the absence of health research on lamb within the U.S. has been the very limited consumption of lamb by U.S. adults (less than one pound per year).

When smaller scale studies of food and health have included lamb, this food has traditionally been lumped together within a category called "red meats," and the meats examined in these smaller studies have typically come from conventionally fed animals. Because grass feeding improves the nutritional value of both beef and lamb, and because lambs are smaller ruminants than cows with different physical characteristics, we would expect studies of grass-fed lamb to show unique results and some unique health benefits.