The Health Benefits of Grass Fed Beef

A balanced diet must include carbohydrates, fats (lipids), protein, vitamins, minerals, fibre and water in the correct proportions for age, gender and activity.

Many, often confusing, words are used to describe the importance of lipids for energy storage, insulation and nervous function.

LIPIDS / FATS

Animal fats and vegetable oils are substances known as triglycerides. Triglycerides are made up of three long-chain fatty acid molecules joined to one molecule of glycerol. They are made up of carbon, hydrogen and oxygen atoms, made in the liver and intestines and stored to be released when you need energy.

The carbon atoms in a fatty acid are joined by single or double bonds to form a chain. If all the bonds are single bonds, the fat is described as ‘saturated’, if there are some double bonds, ‘unsaturated’. A fatty acid with one double bond is ‘monounsaturated’, with more is ‘polyunsaturated’. The carbon atoms are numbered from the end of the chain, the position of the double bonds varying, giving rise to the terms omega-3 and omega-6 fatty acids.

CHOLESTEROL is another lipid, essential for health. It is made in the liver, enables the body to make hormones such as oestrogen and testosterone and is an integral part of all cell membranes.

These lipids, triglycerides and cholesterol, do not dissolve in the blood but are transported in the bloodstream, combined with proteins, as lipoproteins.

It is known that excess consumption of saturated fats is linked with cardiovascular disease (CVD). The level of cholesterol in the blood influences the likelihood of CVD.

LIPOPROTEINS

There are two types of lipoprotein.

High-density lipoprotein (HDL) carries cholesterol back to the liver to be removed from our bodies. In this way it reduces the risk of CVD.

Low-density lipoprotein (LDL) carries cholesterol which accumulates as plaque inside the blood vessels, narrowing their lumen, raising blood pressure and increasing the risk of CVD and heart attack.

Diet and lifestyle both affect the levels of HDL and LDL in the blood.

THE IMPORTANCE OF EATING MEAT

Meat is an excellent source of protein, providing all the essential amino acids which the body cannot produce and must obtain from food. Red meat is a particularly good source of iron to transport oxygen as oxyhaemoglobin, zinc for a strong immune system, reproductive health and healthy skin and vitamin B12 for the nervous system. Lean meat should be consumed as part of a balanced diet, with plenty of fruit and vegetables.

Meat contains both saturated and unsaturated fats. In cattle, the proportion of omega-3 and omega-6 fatty acids is influenced by the breed and how they are fed.

OMEGA-3 and OMEGA-6 FATTY ACIDS

A low ratio of omega-6:omega-3 gives greater health benefits.

We are indebted to the late Richard Young of The Sustainable Food Trust and  his sister Rosamund of Kite’s Nest Farm, Broadway, Worcestershire for directing  us to the two  learned articles from which the following is taken.

The importance of the ratio of omega-3/omega-6 essential fatty acids

‘Excessive amounts of omega-6 polyunsaturated fatty acids (PUFA) and a very high omega-6/omega-3 ratio as found in today’s Western diets, promote the pathogenesis of many diseases including CVD, cancer and inflammatory and autoimmune diseases whereas increased levels of omega-3 (a low omega-6/omega-3 ratio) exerts suppressive effects.’

A. P. Simopoulos The Centre for Genetics, Nutrition and Health, 2001 S Street, N. W., Suite 530, Washington DC 20009 USA.  Biomedicine and Pharmacotherapy 56 (2002) 3

A review of fatty acid profiles and antioxidant content of grass-fed and grain-fed beef.

‘Research spanning three decades suggests that grass-based diets can significantly improve the fatty acid (FA) composition and antioxidant content of beef….. Grass-based diets have been shown to enhance total conjugated linoleic acid (CLA)(C18:2) isomers, trans vaccenic acid (TVA) )C18:1 t11) a precursor to CLA and omega-3 (n-3) FAs on a g/g fat basis. Whilst the overall concentration of saturated fatty acids (SFAs) is not different between feeding regimes, grass finished beef tends towards a higher proportion of cholesterol neutral stearic acid (18:0) and less cholesterol elevating SFAs such as myristic (C14:0) and palmitic (C16:0) FAs. Several studies suggest that grass based diets elevate precursors  for vitamins A and E as well as cancer fighting antioxidants such as glutathione and superoxide dismutase (SOD) activity compared with grain fed contempories. Fat conscious consumers will also prefer the overall lower fat content of a grass fed beef product. Consumers (also) should be aware that the differences in FA content will give grass-fed beef a distinct flavour…..

Daley et al College of Agriculture, California State University Chico, CA USA  Nutrition Journal 2010 9:10.

LINOLEIC ACID or CONJUGATED LINOLEIC ACID..some confusion?

Linoleic acid is a fatty acid with 18 carbon atoms and two double bonds, at C9/C12. The double bond at C12 makes it an omega-6 acid.

Conjugated linoleic acid, also has 18 carbons, 2 double bonds but the double bonds are at alternate positions, eg C10/C12,  C9/C11

The lower case ‘c’ and ‘t’ in the abstract below refer to the configurations ‘cis’ and ‘trans’, affecting the 3-D shape of the molecule. Conjugated linoleic acid has many (20+) different forms or isomers.

It is this subtle difference in 3-D structure, the relative positions of the double bonds which makes them different molecules, with different properties. This causes them to have very different effects in the body.

The following is taken from Ledesma-Amaro and Nicaud, Progress in Lipid Research, Volume 61 January 2016 40-50

‘The CLA isomer c9,t11 appears to be responsible for improving muscle growth, while the t10, c12 isomer prevents lipogenesis, that is, the storage of fat in adipose tissue. Early investigations using CLA led to the realization that this set of compounds has multiple biological effects such as reductions in plasma lipoproteins and lipids and atherosclerosis and body fat accumulations’

So.. GRASS-FED,  GRASS-FINISHED  ABERDEEN ANGUS BEEF, because of  its composition, has:

* a higher ratio of omega-3 fatty acids, which have

* a suppressive effect on CVD, cancer, autoimmune and inflammatory disease

* more precursors of vitamins A and E

* more antioxidants

* may increase muscle growth, reduce adipose/fat tissue

* HAS A SUPERB, UNMATCHED FLAVOUR