Posted by ProPortion Foods Blog on Sep 13, 2017 in Muscle, Protein, Sarcopenia
Age-related muscle loss is one of greatest health issues for older adults. Up to a third of people over 50 experience sarcopenia – the age-related loss of muscle mass and strength. This can lead to many other health complications. However, it can also be prevented and managed with just a few simple interventions.
Sufficient muscle mass is essential for health and wellbeing at any age. One of the key roles of muscle is utilisation of carbohydrates for energy production. More muscle mass means more is used for energy, instead of being stored as fat.
Muscle mass can protect against conditions such as diabetes, cardiovascular disease, premature ageing and poor cognitive function. Unfortunately, many older adults experience sarcopenia, which increases the risk of illness and injury.
When people are inactive for any reason, muscle can waste away. This is known as muscle atrophy or muscle loss.
One of the most common causes of muscle loss is ageing. There are multiple factors that cause age-related muscle loss. It’s believed that a reduction of testosterone and growth hormone combined with an increase in pro-inflammatory cytokines play a big role (1).
There are other causes of muscle loss aside from ageing. Significant injuries, malnutrition, stroke, long-term steroid use and general inactivity can all lead to atrophied muscles. Conditions that restrict movement can also contribute.
Unfortunately, muscle loss can have a significant impact on health and wellbeing.
Muscle loss can negatively impact on health in a number of ways. By losing muscle mass, people are likely to gain body fat instead. This is due to the reduced carbohydrate usage by the muscles, leading to more energy being stored as fat.
People may also experience stiffer joints with muscle loss. This will make it harder for them to move around, which contributes further to muscle loss and fat gain.
This may lead to other health conditions and complications, including cardiovascular disease, diabetes and arthritis. Many of these can become serious or even fatal if left untreated. It is essential to intervene in the early stages of muscle loss, to slow or even reverse the process.
It’s possible to halt and even reverse muscle loss through simple interventions. By using the right nutrition and exercise, muscles can grow and regain strength.
One of the most important interventions is to consume sufficient protein to meet dietary needs. Research suggests that eating similar quantities at each meal is more effective than a large intake in one meal (2).
Keeping physically active is essential for maintaining muscle mass. Even small, regular movement can help in those with limited movement. Research has demonstrated that even 15 minutes of cardiovascular exercise can stimulate muscle growth (3).
Ideally, resistance exercise is included so that muscle strength can be restored. One study demonstrated that just 3 resistance-training sessions per week for 12 weeks could increase muscle strength (4).
These interventions are inexpensive but highly effective in preventing and reversing age-related muscle loss.
Sarcopenia and muscle loss can cause many health issues. However, simple interventions such as nutrition and exercise provide a safe, easy and effective way to prevent and reverse muscle loss.
Posted by ProPortion Foods Blog on Sep 7, 2017 in Muscle, Protein
Did you know that the human body is comprised of about 16 per cent protein[1]? Proteins are complex molecules which are required for the structure, function, and regulation of the body’s tissues and organs[2].
The functions of protein in the human body are grouped into five categories[3]:
Long chains of amino acids are the building blocks of protein, which can be broken down into 2 categories.
Complete and incomplete proteins can be further examined and ranked by their quality. Protein quality is determined by either PDCAAS (protein digestibility-corrected amino acid score) or DIAAS (digestible indispensable amino acid score). Both of these scores were created by the Food and Agriculture Organization of United Nations (FAO), and it is their recommendation that DIAAS be used as the preferred method[4].
The DIAAS uses a mathematic equation to calculate the “individual indispensable amino acids in the dietary protein relative to human reference amino acid requirement pattern” [5]. Foods are then assigned a score, and ranked. Unlike DIAAS, PDCAAS truncates values to 1, so it isn’t able to account for minor variations like DIAAS[6].
How much is enough protein to consume?
EAR & RDI
The Australian and New Zealand governments created the Nutrient Reference Values based on currently available scientific knowledge[7]. The research body lists the EAR (estimated average requirement) and RDI (recommended dietary intake) for adults.
Even distribution & higher protein consumption
Recent research into the timing and consumption of protein suggests that even distribution throughout the day, with 25g-30g at each meal, can maximize muscle protein synthesis[8]. This amount of protein is significantly greater than the current RDI for women.
This study is of particular interest to older adults who are encouraged to consume considerably higher than the minimum protein requirements for optimal health[9]. The EAR and RDI do not “account for the compensatory loss of muscle mass”9 or lower rates of protein synthesis in older adults.
An increase in dietary protein for older adults has shown to increase lean mass gain, when combined with resistance exercise. 40 per cent of Australians in their 70s experienced a fall in the past 12 months[10]. An increase in lean muscle mass from dietary protein and resistance exercise has been found to reduce the incidence of falls among this cohort[11].
[1] https://www.britannica.com/science/human-nutrition
[2] https://ghr.nlm.nih.gov/primer/howgeneswork/protein
[3] http://www.livestrong.com/article/407936-what-are-the-functions-of-protein-in-the-human-body/
[4] http://www.ift.org/Food-Technology/Daily-News/2013/March/07/FAO-proposes-new-protein-quality-measurement.aspx
[5] http://www.fil-idf.org/wp-content/uploads/2016/03/IDF-Factsheet-Interpretation-of-Protein-Quality.pdf
[6] https://www.arlafoodsingredients.com/the-whey-and-protein-blog/research/determining-protein-quality-the-current-state-of-play/
[7] https://www.nrv.gov.au/
[8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2760315/
[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555150/
[10] http://www.racgp.org.au/afp/2012/december/falls-prevention/
[11] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3136106/
Posted by ProPortion Foods Blog on Jul 3, 2017 in Muscle
Type 2 diabetes is a metabolic condition that occurs progressively, beginning with decreased insulin sensitivity in cells, known as insulin resistance, leading to pre-diabetes. Without intervention pre-diabetes will eventually progress to overt type 2 diabetes. One of the most distinctive traits of type 2 diabetes is that it can be managed by diet and lifestyle modifications. In some cases, individuals are able to completely reverse the symptoms.
In type 2 diabetes sufficient insulin is produced initially; the problem lies with the action of insulin on target cells. Instead of producing the usual effects of insulin – that is the uptake of glucose from the blood into cells to provide energy – the effects of insulin are blunted and glucose remains in the blood. In turn, the pancreas produces more insulin in an attempt to maintain normal blood glucose levels, and eventually it cannot keep up with this demand. The end result is not only hyperglycaemia but also high blood insulin levels. This state is referred to as pre-diabetes. At this stage blood glucose levels are slightly elevated, yet not to the levels seen in overt diabetes.
In an attempt to normalise these high blood glucose levels, the pancreas over compensates and secretes more insulin. This state can last for years until continued over production of insulin eventually degrades and damages pancreatic beta cells resulting in overt type 2 diabetes. At this point there is both a decrease in the effectiveness of insulin and reduced insulin production (1).
The majority – around 80% – of glucose uptake after a meal occurs in muscle tissue, making muscle an important site of glucose disposal. Increasing muscle mass can decrease progression of insulin resistance regardless of overall body size.
It has been demonstrated in observational studies that increased muscle mass may reduce the risk of type 2 diabetes. A cross sectional analysis of the National Health and Nutrition Examination Survey III using data from 13,644 participants concluded that higher percentages of muscle mass were associated with increased insulin sensitivity; researchers also noted an inverse relationship between muscle mass and risk of pre-diabetes (2).
This is significant for both prevention and management interventions. Regular resistance exercise and preservation of muscle mass, especially as we age, could in fact lower the risk of developing diabetes and other metabolic diseases (3, 4). Unfortunately, this can be rather challenging for those with type 2 diabetes as they are prone to muscle atrophy, likely resulting from decreased activity of anabolic hormones. This is especially prevalent in elderly diabetics (5). For this reason, it is important to consider dietary management to accompany increased and regular exercise.
Inactivity contributes significantly to the development of type 2 diabetes. Physical activity and regular exercise can enhance blood glucose control and reduce diabetes risk.
Even 30 minutes of moderate exercise per day, such as brisk walking, 5 days a week can reduce diabetes risk by 30% (7). However higher intensity exercise such as running, cycling, swimming for longer durations and the addition of resistance exercise is likely to achieve better results (3, 4).
Sarcopenia (defined as reduced muscle mass through ageing), and sarcopenic obesity (which is the presence of sarcopenia concurrently with obesity), are known risk factors for insulin resistance and type 2 diabetes respectively (5, 10, 11). Preservation of muscle mass is of particular importance in the elderly, especially when either sarcopenia or sarcopenic obesity are present. A structured exercise and dietary intervention can significantly decrease the risk of developing type 2 diabetes in these populations.
Any intervention program for pre-diabetes and type 2 diabetes should focus on both physical activity and diet. A diet containing insufficient protein is likely to have a deleterious effect on muscle mass. This is especially relevant in the elderly, who typically do not consume sufficient protein to help support muscle growth (12). A protein rich diet, when coupled with resistance exercise, has also been shown to improve body composition in type 2 diabetics (13, 14).
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2. Srikanthan P, Karlamangla AS (2011) Relative muscle mass is inversely associated with insulin resistance and prediabetes. Findings from the third National Health and Nutrition Examination Survey. The Journal of Clinical Endocrinology & Metabolism; 96, 2898-903.
3. Colberg SR, Albright AL, Blissmer BJ, Braun B, Chasan-Taber L, Fernhall B, et al. (2010) Exercise and type 2 diabetes: American College of Sports Medicine and the American Diabetes Association: joint position statement. Exercise and type 2 diabetes. Medicine and science in sports and exercise; 42, 2282-303.
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8. Group DPPR (2015) Long-term effects of lifestyle intervention or metformin on diabetes development and microvascular complications over 15-year follow-up: the Diabetes Prevention Program Outcomes Study. The Lancet Diabetes & Endocrinology; 3, 866-75.
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14. Wycherley TP, Noakes M, Clifton P, Cleanthous X, Keogh J, Brinkworth G (2010) Timing of protein ingestion relative to resistance exercise training does not influence body composition, energy expenditure, glycaemic control or cardiometabolic risk factors in a hypocaloric, high protein diet in patients with type 2 diabetes. Diabetes, Obesity and Metabolism; 12, 1097-105.
15. Wycherley TP, Moran LJ, Clifton PM, Noakes M, Brinkworth GD (2012) Effects of energy-restricted high-protein, low-fat compared with standard-protein, low-fat diets: a meta-analysis of randomized controlled trials. The American journal of clinical nutrition, ajcn. 044321.
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