Dairy proteins: essential ingredients for keeping sarcopenia at bay

Sarcopenia refers to the age-related degenerative loss of muscle mass. Faced with an ageing population, sarcopenia prevention is one of the most effective strategies in preserving independence and health among the elderly. Milk proteins and whey play a crucial role in preventing the disease.

Contents:

• Sarcopenia: Definition and causes
• Nutritional intervention in preventing sarcopenia
• The nutritional benefits of milk proteins used as protein supplements
• Armor Protéines' solutions

SARCOPENIA: DEFINITION AND CAUSES

Sarcopenia is the gradual loss of strength and muscle mass that occurs as part of the ageing process.

A few figures to clarify:

• Humans lose 50% of their muscle mass between the ages of 20 and 80.
• Prevalence rates for sarcopenia are 25% before the age of 70 and over 50% past the age of 80.
• This loss of muscle is exacerbated by a sedentary lifestyle as well as malnutrition, which is thought to affect around 10% of elderly people living in their own homes, and 30% to 60% of those living in homes or other institutions.

Sarcopenia and malnutrition contribute to a decrease in muscular strength, trigger balance issues and increase the risk of falling in those with the condition.

More specifically, sarcopenia points to an imbalance between proteolysis (protein deterioration) and proteosynthesis (protein synthesis).

That's why it's particularly important to work to optimise nutritional intake and the biological efficiency of food protein at every stage of life.

NUTRITIONAL INTERVENTION IN PREVENTING SARCOPENIA

Regular physical exercise and a variety of nutritional factors (proteins, leucine, glutamine, citrulline, vitamin D, omega-3 fatty acids) play a key role in preventing sarcopenia.

Recommended daily protein intake for the elderly is set at 1 to 1.2g per kilo of body weight per day. 15% to 20% of total energy consumed must come from protein. The quantity, quality and ways in which this protein is taken are important factors to consider in order to optimise the efficiency of food proteins, particularly in the elderly, whose digestive capacities differ from those of young subjects.

Milk proteins play a key role in preventing sarcopenia due to their relatively high leucine content. This branched-chain essential amino acid is particularly important in:

• Regulating protein renewal throughout the ageing process,
• Maintaining muscle mass.

Whey protein supplements have been shown to significantly improve muscular strength. Recent studies show that the quality of the proteins consumed at each meal impact on the efficiency of these proteins:

• Eating 25g to 30g of protein at each meal maximises the biological efficiency of protein in synthesising muscle.

Protein supplements taken with fortified meals are a good way of preventing sarcopenia. Another clinical study of 60 elderly subjects with sarcopenia showed that taking whey protein, vitamin D and vitamin E supplements over a six-month period significantly increased muscle mass and strength and protein synthesis blood markers.

The elderly need significantly higher amounts of amino acids in their plasma to stimulate muscular protein synthesis and inhibit proteolysis.

THE NUTRITIONAL BENEFITS OF MILK PROTEINS USED AS PROTEIN SUPPLEMENTS FOR THE ELDERLY

Influence of milk protein digestibility and essential amino acid composition on protein synthesis

Protein quality impacts on muscle synthesis efficiency. Food protein digestibility and essential amino acid composition influence how efficient they are in synthesising muscle.

Several studies have shown that it's possible to boost muscle protein synthesis when the consumption of protein results in an intense, quick-fire spike in some amino acids (leucine in particular) in the blood. Amino acids in the blood depend on protein digestibility, the food matrix and the amount of time the protein spends in the stomach. Texture and matrix type (solid or liquid) both impact on protein digestibility.

Milk proteins boast incredibly high digestibility rates. The DIAAS (digestible indispensable amino acid score) for milk proteins is one of the highest in existence.

The DIAAS also provides information on the quantities of essential amino acids transmitted to the organism per gram of proteins consumed. The speed at which whey proteins and caseins are digested differs:

• Caseins coagulate in the stomach, and are more slowly digested.
• Whey proteins are digested more quickly, and trigger a spike of amino acids in the blood, along with a short, sharp burst of muscle protein synthesis.

Essential amino acid/calorie ratio

The concept of an essential amino acid/calorie ratio should also be taken into account.

High-quality proteins such as milk proteins have a major advantage: they provide a high amount of essential amino acids with fewer calories compared to lower-quality proteins.

Essential amino acids, and leucine in particular, are important in stimulating synthesis and inhibiting muscular deterioration. Leucine, for example, plays a key role in stimulating the mTOR pathway responsible for regulating cell proliferation and protein synthesis.

Milk and whey proteins contain high quantities of essential amino acids, including leucine.

To conclude, thanks to their compositional properties and digestibility, milk proteins are a powerful way of nutritionally enhancing diets in a bid to prevent and treat sarcopenia.

ARMOR PROTEINES' SOLUTIONS

Combining technological expertise with the latest scientific data, Armor Protéines offers a range of dairy ingredients that are natural, Clean Label, and perfect for nutritionally enriching food matrices.

In addition to their nutritional benefits, these ingredients boast excellent texturising properties, allowing manufacturers to optimise acceptability and flavour in a wide range of different products and food matrices, whether solid or liquid.

Their excellent solubility and dispersibility ensure they can be used for a wide range of applications in a variety of different matrices:

• Bars,
• Blended recipes,
• Dairy-based desserts,
• Spreads,
• Drinks.

Learn more about Armor Protéines' functional dairy ingredients →

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