Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Wellness Foods Europe Protein Protein – a nutrient that has received mixed press over the years Claire Mac Evilly, Communications Manager, Food for Health Ireland Photo©:Fotolia/Elena Schweitzer When you open the nutrition books, the first thing you learn about is the macronutrients – proteins, fats and carbohydrates and while it may seem that dietary advice is always changing about these nutrients, their importance in our diet has not changed. In terms of protein, the nutritional and scientific focus has clearly shifted onto the source or type of protein and the functional benefits of certain proteins. The reality is that that most of us eat more protein than we need, as it is found in many foods that make up our daily diet including meat, poultry, fish, eggs, nuts and dairy products. But are we eating the right type of protein and are all proteins created equal? Proteins are part of every cell, tissue and organ in our bodies. These body proteins are constantly being broken down and replaced. The protein in the foods we eat is digested and later used to replace these proteins in our bodies. The ‘building blocks’ of protein are known as amino acids. There are 20 different amino acids that combine together to make 4 | Wellness Foods Europe – April/May 2014 all types of protein. Some of these amino acids can’t be made by our bodies, so these are known as essential amino acids. It’s essential that our diet provide these. In the diet, protein sources are differentiated according to how many of the essential amino acids they provide: – A complete protein source is one that provides all of the essential amino acids. These are high quality proteins. Animal-based foods; for example, meat, poultry, fish, milk, eggs, and cheese are considered complete protein sources. – An incomplete protein source is one that is low in one or more of the essential amino acids. Complementary proteins are two or more incomplete protein sources that together provide adequate amounts of all the essential amino acids. For example, rice contains low amounts of certain essential amino acids; however, these same essential amino acids are found in greater amounts in dry beans. Simi larly, dry beans contain lower amounts of other essential amino acids that can be found in larger amounts in rice. Together, these two foods can provide adequate amounts of all the essential amino acids the body needs. The most health-conscious consumers are becoming more and more aware of the bene fits of protein above and beyond basic nutrition. This is leading to a steady increase in the demand for high quality protein particularly from within the dairy industry. Whey proteins up until recently have been the dietary fuel of choice for body builders and elite athletes, but they are slowly making their way into mainstream consumer foods and beverages. High protein, low GI diets have blown hot and cold among weight conscious consumers and nutrition experts over the past decade. However, late 2010 saw the publication of the results of the Diogenes study, which has since provided an unprecedented boost for such diets. Heralded as the world’s largest dietary study, Diogenes investigated the optimum dietary composition for the prevention and treatment of obesity. The results showed that a high-protein, low-glycemic index (GI) diet was the single most effective diet for weight management. The researchers suggest diets with 25 % of calories from high-quality, low-fat protein sources. But it’s not just about the macro nutrient. Scientists have recently begun to look at chains of amino acids called peptides. Peptides are formed when proteins are broken down by enzymes in the gut or by fermentation or ripening during food processing. Some of these peptides are ‘bioactive’, in other words, they have an effect on systems in the body. Specifically, they may positively affect the cardiovascular, digestive, endocrine, immune and nervous systems. For this reason the potential of these peptides to have positive health benefits has aroused interest among not only the scientists but also the food industry as they see the benefits in de- Photo©:Fotolia/Janine Fretz Weber Protein Wellness Foods Europe veloping health promoting functional foods containing bioactives. Bioactive peptides of particular interest are found in foods including peas, soya, seaweed and milk. Ireland currently processes 5.6 billion litres of milk annually but this figure is set to rise by 50 % by 2020. Eighty five per cent of milk produced in Ireland is exported. In fact, Ireland produces enough milk to feed 52 million people; roughly 11 times the national population. Milk is a valuable and highly complex biological material, composed of multiple constituents such as proteins, carbohydrates, fats, vitamins and minerals. Milk contains two primary sources of protein, casein (80 %) and whey (20 %) which behave differently in the body. Casein is digested slowly and therefore proteins are slowing broken down into amino acids. On the other hand whey protein is digested quickly. The reason milk proteins are of interest is because of their amino acid composition and their sequencing which makes them particularly active. Milk is also easily available in large quantities, and it is easier to work with than solid protein-rich foods like meat. Milk proteins exert a wide range of nutritional, functional and biological activities. One potential health benefits of different bioacApril/May 2014 – Wellness Foods Europe | 5 Photo©:Fotolia/kubais Wellness Foods Europe Protein tive milk peptides include reducing the risk of type two diabetes. Type 2 Diabetes (T2D) is a serious condition with 366 million people globally living with the disease. The global prevalence of diabetes is forecast to continue to increase, while the World Health Organisation projects that diabetes will be the 7th leading cause of death in 2030. Diabetics have high blood sugar (blood glucose) either because the pancreas does not produce enough of the hormone insulin or because cells in the body do not respond to the insulin that is produced. Milk proteins given to diabetics in a research study which is part of the Food for Health Ireland project based in University College Dublin have shown some promising effects in keeping the patients blood glucose levels within a normal range and this research is ongoing. Formulations derived from milk have also shown promising effects in reducing the risk of the age related progressive decline of skeletal muscle mass known as sarcopenia and building muscle in athletes. Healthy active ageing and improving sports performance share similar mechanisms in terms of muscle health and development. As we age the amount of muscle and lean tissue mass we have begins to decrease. This can lead to frailty, disability and loss of independence in older adults. Conversely, high performance athletes generally try to increase 6 | Wellness Foods Europe – April/May 2014 muscle mass and muscle function which then has to recover and adapt quickly to sustain and improve optimal performance. Many of the nutrient and metabolic regulators of these effects on muscle in ageing and high performance overlap. Can milk, specifically the proteins within milk, help older people and athletes to rebuild their muscle and to recover quickly for the next performance, respectively? Further research is required but the potential is there. Other new areas where research about bioactive peptides is underway include inducing satiety, cognitive function, memory-related diseases and mood control. Demonstrating the impact of bioactive peptides on these disease states is only the beginning. The challenge will be to scale up the production of the peptides, their bioavailability, safety and putting them into other foods that people will buy. Also further studies are needed to assess the bioactive mechanisms of action and researchers will be using new nutrigenomic techniques, for example proteomics and metabolomics. This research area is currently considered highly challenging and will revolutionize the protein research in the near future. Another issue with functional foods products containing novel bioactive is if any health-related claims are attached to the products. Currently healthy claim regulations seem to vary greatly in different countries but regional and international harmonization processes are underway. So the next time you pour your milk into your cereal or have a glass of milk – look carefully. There is a lot more going on in its proteins than meets the eye! The Author: Claire Mac Evilly, Communications Manager, Food for Health Ireland, University College Dublin Tel + 353 1 7162394 E-Mail [email protected], www.fhi.ie