High Protein Foods And The Elderly

About protein

Protein is an essential building block of life. Contained in every single cell and involved in every process in the human body, proteins carry out most of the work that our cells must perform to keep us alive. 

Proteins are made up of single molecules called amino acids which combine like blocks of lego to form proteins of different shapes. The arrangement of the blocks determines the function of the protein, whether it be destined to form skin, hair, blood, bone, or other substance such as hormones.

Protein is found in both plant foods such as vegetables, legumes, grains and fruits, and animal foods such as meat, cheese, fish and eggs. We must eat enough protein in order to supply all of the amino acids needed to meet the demands of all the various cellular processes that sustain life. When the protein that we eat is digested it gets broken down into single amino acids, which the body then reassembles to make a new protein.

Sources of protein

Most foods contain a combination of protein, carbohydrates and fats. These ‘macronutrients’ provide calories for energy, as well as other substances needed in relatively large quantities for our bodies to function well, such as amino acids and fatty acids. Some foods are abundant in just one macronutrient whilst others are high in two macronutrients and are harder to classify. 

Meat ranks highest among protein-rich foods. However the proportion of protein and fat varies from animal to animal and by the cut of meat. For example, 63% of the calories in chicken breast come from protein and 37% from fat, whereas beef mince is around 62% fat and 38% protein.¹ Dairy foods are a good source of protein but also vary considerably by fat content. 

Grains, pulses and legumes are classified as carbohydrate foods but also supply decent amounts of protein and low amounts of fat. Most pulses and legumes are approximately 60-65% carbohydrate and 21-25% protein.² One exception is Soy, which unlike other legumes stands out as being low in carbohydrates (about 20%) and high in both proteins (35%), and fat (40%). Cereal grains such as wheat, rice and oats are about 50-70% carbohydrates but still contain 7-13% protein which contributes towards your daily intake.³

Importance of protein

There are 20 amino acids that our bodies combine in various ways to make every single protein that it needs. Our body can make 11 of these amino acids from other substances, but 9 must be obtained through the food we eat. These are known as essential amino acids (EAAs) because it is essential that we consume enough of them. When there is Insufficient dietary intake of protein the body begins to break down its own muscle tissue in order to liberate EAAs necessary to keep other essential bodily processes going. Over time this causes visible muscle wasting and muscular weakness. Ingesting essential amino acids stimulates muscle tissue growth on the other hand, otherwise known as muscle protein synthesis.

Foods which come from animals contain all 9 EAAs in plentiful amounts. These are often referred to as being ‘complete’ protein sources. Vegetarian foods do contain all 9 EAAs but in lower quantities. You would have to eat enormous quantities of beans to meet your body’s requirement for the EAA methionine for example, but grains and seeds eaten in reasonable quantity will supply enough. In fact, seeds contain more methionine per gram of protein than meat! Conversely, you can get enough lysine from eating vegetables and beans, whereas grains, seeds, and nuts are a very poor source of this EAA.⁴ For this reason, vegetarians are often advised to combine rice with beans, bread with nut butter, and lentils with chick peas. Eaten together, these pairings make a ‘complete protein’ with all 9 EAAs in sufficient amounts. Of course, different foods are typically combined at meal times - it would make for a very bland diet to eat beans alone at one meal and rice at the next!

How much protein do I need?

Eating a varied diet with enough calories to meet your body’s energy requirements will supply you with enough protein from plant and animal sources. Even those following a vegetarian diet can obtain all the protein they need provided they eat a variety of vegetables, fruits, grains, beans, pulses, nuts, and seeds.

The amount of protein you require each day is calculated by multiplying your body weight in kilograms by 0.8 grams; an adult weighing 75 kg would need to eat around 60 grams of protein per day. This protein intake level is considered adequate for an average adult male or female. However, protein requirements can vary quite a bit between individuals depending on activity level, age, health status, and other dietary factors. For those critically ill or recovering from serious injury, a higher intake of 1.5 grams of protein per kilo bodyweight is recommended. And up to 2 grams per kg may be necessary for frail older adults who are unable to maintain their body weight.⁵

Sarcopenia of ageing

As we age, our muscles become smaller and weaker. This decline in skeletal muscle begins around the age of thirty and happens at about a rate of 3-8% muscle mass lost per decade, slowly at first and then speeding up after age sixty.⁶ The name given to this phenomenon is the Sarcopenia of ageing. Sarcopenia is a significant cause of frailty in older adults and is associated with an increased risk of falls and vulnerability to injuries, which in later life can be disabling.⁷ Sarcopenia also contributes to gradual weight gain, which is common in late adulthood. This is because muscle is a highly metabolically active tissue that uses energy. Having lower muscle mass, therefore, means the body requires fewer calories each day. 

Sarcopenia happens due to normal ageing processes but is accelerated by inadequate diet and sedentary lifestyles. It is quite common for seniors to eat less than they need for various reasons, including reduced appetite, dental issues, less pleasureful food due to age-related loss of taste and smell, and restricted access to food caused by mobility limitations and social isolation. Some may even deliberately avoid protein-rich foods because they are concerned with the saturated fat and cholesterol content of meat, cheese, and eggs.  

Recommended high protein foods for elderly

Clinical trials suggest that high protein intakes help to preserve muscle mass and strength in older persons. According to one study, up to 140% more protein is required to stimulate muscle protein synthesis (muscle growth) in an older person compared to a young adult.⁸ One reason is that as we age, protein is less absorbed following digestion. 

Not all proteins are digested equally. Animal protein is digested faster and more completely than plant protein, with soy protein being the only exception. 100% of the amino acids found in eggs, milk, and soy protein isolate get absorbed into the bloodstream, compared to 40% in whole wheat.⁹ Casein, found in milk solids, and whey, found in the liquid portion of milk, is considered the gold standard of protein in terms of amino acid profile and overall digestibility.¹⁰ However, whey is digested more quickly, which is why it is the first choice of bodybuilders looking to maximize muscle gains. Yogurt also ranks highly, with a protein digestibility score of 95%.

Increased dairy consumption seems to offer some protection against sarcopenia. Seniors with the highest intakes of yogurt, milk, and cheese have been found to have greater preservation of muscle mass and strength and lower risk of frailty compared to those with lower intakes.¹¹ Low dietary intake of vitamin D, vitamins B1 and B2, potassium, magnesium, and phosphorus have also been associated with sarcopenic muscle loss, and dairy foods are an excellent source of these essential nutrients in addition to protein.^12,13

Skimmed milk, plain and greek yogurt, and curd cheeses such as ricotta, cottage cheese, and quark are good choices. Rind and hard cheeses should be eaten in moderation, however, due to their high cholesterol and saturated fat content.

Fish is also a good low-fat protein source, which should form part of a healthy balanced diet. It is recommended that people of all ages consume two portions of fish per week, one of which should be oily.¹⁴ Oily fish such as salmon, mackerel, or sardines are a great source of vitamin D and omega-3 fatty acids, which help to protect heart and brain health. Omega-3 fatty acids have also been linked to improved muscle mass and strength in individuals with sarcopenia.¹⁵

High protein diet tips for the elderly

Some studies have shown that muscle protein synthesis is maximally stimulated when a minimum of 25-30 grams of protein is ingested at each meal and that consuming more protein than this in a single sitting is not better for preserving muscle.¹⁶ A typical day’s menu that would supply 30+ grams of protein in each meal could look like this:

Breakfast

2 scrambled eggs,

2 slices wholemeal toast,

250 ml semi-skimmed milk

Lunch 

Baked potato,

1 tin of tuna,

Salad

Dinner

150 g chicken breast,

1 cup cooked broccoli

It can be challenging however for an older person with a low appetite to manage three meals per day. Older adults may not eat enough to meet their protein and other nutrient requirements because they simply don’t feel hungry. Protein is the most satiating macronutrient, meaning it keeps us fuller for longer compared to carbohydrates and fats, whereas carbohydrates and fats stimulate taste receptors to a greater extent than protein.17 Taste becomes blunted in old age, and it is not uncommon for the elderly to favour sweet, salty tastes and snacks high in sugar, salt, and fat. These can displace more nutritious fare, leading to a diet that is calorie dense and nutrient-poor. A protein supplement, therefore, can be a good strategy to meet the increased protein requirements of old age in adults with poor appetite. A 35-gram serving of either soy or whey protein isolate mixed with water will supply 31 or 20 grams (respectively) of highly digestible protein containing all essential amino acids.

However, dietary supplements, including protein powders, should not be substituted for whole foods but should complement an otherwise healthy balanced diet. Seniors are advised to prioritise lean meat, fish, low-fat dairy, vegetables, beans, and pulses and reduce their intake of starchy carbohydrates such as bread, rice, pasta, breakfast cereals, and sugary foods, which provide calories and bulk to meals but have low overall nutritional value. 

FAQs

What happens if the elderly have too much protein? 

Increasing protein consumption can worsen kidney problems. Seniors with kidney disease should not increase their protein intake before consulting a doctor.

How much protein does an 80-year-old need?

Experts in protein and ageing recommend a protein intake between 1.2 and 2.0 g/kg/day or higher for elderly adults.

What happens if an elderly lack protein?

Protein is a key nutrient for muscle health in elderly adults. Lack of protein is associated with the progressive loss of muscle mass and function (sarcopenia) that occurs with ageing.

Does the elderly needs more protein than younger adults? 

Even healthy seniors need more protein than when they were younger to help preserve muscle mass.

Summary

One of the major threats to maintaining independence and quality of life in later years is the progressive loss of muscle mass, strength, and function that occurs with ageing. Higher protein intakes are needed to stimulate muscle growth and repair as we age. However, even the very elderly can increase their muscle mass and strength through physical exercise together with an adequate intake of protein and other nutrients.² Animal protein is best in terms of overall quality and digestibility, and dairy, in particular, seems to be associated with the preservation of lean muscle mass. However, a balanced diet that includes protein from both plant and animal sources is recommended to ensure an adequate intake of vitamins, minerals, and other essential nutrients associated with healthy ageing.