Nutrition in the Elderly

As individuals get older, their bodies undergo a lot of changes. They may experience reduced muscle mass, reduced stomach acid, and decreased kidney function. Low levels of stomach acid negatively affect the absorption of nutrients such as magnesium, iron, calcium, and vitamin B12 and decreased kidney function further disrupts this process [1, 2].

The kidneys play a role in filtering nutrients and harmful particles from the blood. They also promote the re-absorption of nutrients the body needs into the blood [1]. Decreased kidney function means that the body receives an inadequate amount of nutrients. In addition, the body’s ability to stimulate thirst and hunger may decrease with age and this can worsen nutritional deficiencies, cause dehydration, and result in unexpected weight loss. The combination of these factors is also linked to age-related losses in muscle mass (muscle wasting) because the body begins to use muscle protein to supply vital organs with nutrients that are lacking.

Muscle loss, which is also known as sarcopenia, is a natural part of the aging process. After the age of 30, muscle mass may gradually begin to decrease by 3-5% every 10 years [3]. However, nutrient deficiencies may speed up this process. Another factor that contributes to the onset of sarcopenia is age-related decreases of testosterone, a hormone that plays a role in the stimulation of protein synthesis for muscle growth [4, 5]. Unfortunately, less muscle leads to weakness and reduced mobility that increases the risk of falling and fracturing bones.

Exercise and Oral Nutritional Supplements

An optimal way to target sarcopenia is through progressive resistance training (PRT), in which an individual gradually heightens the workout routine by increasing weight, repetition, and training techniques to boost muscle mass. This form of exercise also enhances muscle strength and endurance, and research shows that because PRT gradually becomes more challenging, it consistently builds up muscle [6]. More specifically, regular adjustments to the training regimen including the duration and frequency of the sessions, the types of exercises that target each muscle, and the number of repetitions for each muscle group, challenges your muscles and ensures that they become stronger. Indeed, PRT has been shown to help individuals experience significant increases in lean muscle [6].

In addition to exercising, a nutritious diet also helps limit the occurrence of sarcopenia. Protein in particular, is broken down in the body into amino acids that are used to build muscle. With age, the body may struggle to properly produce and break down protein. This means that protein supplementation becomes necessary as people age. One study indicates that supplementation with 1-1.3 grams of protein per kilogram in combination with resistance training is beneficial for older adults [7, 8]. High protein oral nutrition supplements (ONS) are especially useful for older people who may struggle to consume enough protein and calories through their regular diet.

 References

  1. Russell RM. Factors in aging that effect the bioavailability of nutrients. J Nutr. 2001;131(4 Suppl):1359S-61S.
  2. Sipponen P, Maaroos HI. Chronic gastritis. Scand J Gastroenterol. 2015;50(6):657-67.
  3. Chalhoub D, Cawthon PM, et al. Risk of nonspine fractures in older adults with sarcopenia, low bone mass, or both. J Am Geriatr Soc. 2015;63(9):1733-40.
  4. Cruz-Jentoft AJ, Baeyens JP, et al. Sarcopenia: European consensus on definition and diagnosis: Report of the European Working Group on Sarcopenia in Older People. Age and Ageing. 2010;39(4):412–423.
  5. Sakuma K, Yamaguchi A. Sarcopenia and age-related endocrine function. Int J Endocrinol. 2012;2012:127362.
  6. Peterson MD, Sen A, Gordon PM. Influence of resistance exercise on lean body mass in aging adults: a meta-analysis. Med Sci Sports Exerc. 2011;43(2):249-58.
  7. Morais JA, Chevalier S, Gougeon R. Protein turnover and requirements in the healthy and frail elderly. J Nutr Health Aging. 2006;10(4):272-83.
  8. Nowson C, O’Connell S2. Protein requirements and recommendations for older people: A Review. Nutrients. 2015;7(8):6874-99.