Posted by ProPortion Foods Blog on Apr 1, 2019 in Protein
Fancy some termites with your vegies for dinner? They taste rather minty, apparently. Or how about some grasshoppers – the Mexicans enjoy them roasted in chilli and garlic. In China you could try some fishy-tasting scorpions, or Cambodians might try and tempt you with fried tarantulas.
Many cultures have been eating bugs for centuries – including Indigenous Australians with delicacies like witchety grubs. Now, insects’ appeal as a cheap, nutritious and environmentally friendly food source is capturing attention as a potential solution for food security and sustainable agriculture.
By the year 2050 it’s estimated the world’s population will reach 9 billion people. To feed this growing population, current food production will need to nearly double.
But about one billion people around the world are hungry now. And food production is already unsustainable in the face of its ecological impact, climate change, land scarcity, overfished oceans and water shortages.
For this reason, leading organisations including the World Bank, United Nations and EAT Lancet Consortium are calling for radical overhauls of current agricultural and dietary practices.
They say multilevel solutions are needed that embrace and support small scale farmers, biodiversity and local knowledge. This includes widespread agreement that we need to eat more plant food and substantially less livestock for planetary and human health.
Insects rival conventional meat sources for their protein content, while putting significantly less strain on the environment.
Gram for gram, farming insect protein compared to beef needs 8 to 14 times less land, 5 times less water, and produces 6 to 13 times fewer greenhouse gas emissions.
Packed with amino acids, crawly critters are a high-quality protein source. They also deliver other nutrients including healthy fats, minerals such as iron, zinc, potassium and selenium, and vitamins including the B group.
Unlike animal food sources, insects contain fibre – mostly from the chitin in their exoskeleton, making them a good source of prebiotics.
In support, a study from the University of Wisconsin-Madison found that people who ate cricket powder in their breakfast every day for two weeks showed increased abundance of the beneficial bacteria Bifidobacterium animalis in their gut compared to controls who consumed the same breakfast without crickets.
But there are issues with foraging insects from nature for food; for instance, Australian honey ants and wood grubs are now threatened due to overexploitation by indigenous people for restaurants and ecotourism.
For this reason, insect farms are growing in popularity for animal feed or additives to human food. But they still need to overcome the “yuck factor” and pass regulatory tests for food safety.
That hasn’t stopped companies from producing insect-based products, for instance foods enriched from cricket protein seem to be growing in popularity – including cricket protein powder, organic roasted crickets and cricket energy bars.
Don’t fear. For vegans and vegetarians – and people who just can’t stomach the thought of eating insects – there are plenty of other nutritious, plant sources of protein including nuts, legumes, lentils, seeds, quinoa, and even hemp.
Animal protein – particularly whey powder – is popularly endorsed as the best source of amino acids for boosting muscle strength. But a closer look at the research suggests that plant proteins could be just as effective for building and maintaining lean muscle mass.
Whey protein contains more of the amino acid leucine than plant proteins. Extensive research shows that leucine activates muscle protein synthesis – i.e. helps muscle to use the protein. This is thought to explain its superior benefits for building lean muscle and strength after resistance training.
However, the evidence derives from studies of whey protein’s short-term impact over 3 to 4 hours. A recent meta-analysis combined nine studies that compared soy protein with various animal proteins over 6 weeks or more (5 studies tested whey and 4 used beef, milk or dairy protein).
Overall, the analysis found that combining protein supplementation with resistance training exercises (bench press and squat) increased muscle strength. But the effects of soy protein did not differ from whey powder or the other animal proteins.
Looking at whole dietary patterns, the Framingham Third Generation Study found last year that people with lower protein intakes had lower lean mass and muscle strength. But they also found no difference between the different types of protein.
According to Health.com, lead author Kelsey Mangano says, “As long as a person is exceeding the recommended daily allowance for protein, no matter the source in their diet, they can improve their muscle health.”
Losing muscle mass is one of the biggest health challenges of aging. Lean muscle does so much more than endow our bodies with a shapely physique.
Older adults need to maintain lean muscle mass to prevent falls, a major problem in aging that results in physical injury, reduced quality of life, and death.
Muscles store glucose to provide energy and can protect against diabetes and heart disease. Age-related loss of muscle mass can lead to sarcopenia, also associated with reduced quality of life, hospital admissions and chronic conditions like poor lung function and breast cancer risk.
Proteins are made from 20 amino acids arranged in thousands of different combinations. Nine amino acids are “essential” – i.e. we need to get them through dietary sources.
Animal proteins include meat, fish, chicken, eggs, and dairy foods. Protein also derives from abundant plant foods including nuts, legumes, seeds, lentils, grains, and even hemp.
Most plant protein sources are incomplete – i.e. they don’t contain all essential amino acids. Proteins derived from animal sources are complete; hence animal protein was deemed to be superior.
However, eating combinations of plant sources provides a complete protein, and it’s now established that the body can store amino acids, so a whole amino acid contingent doesn’t need to be eaten in one meal.
Most importantly, regardless of the source, research suggests that older adults who eat 1 gram of protein per kg of body weight each day are less likely to suffer disability. Combining this with regular physical movement will yield the greatest benefits.
A new study has found that adults over 84 years who eat more protein are less likely to suffer disability, which is a significant problem in this growing age group.
Researchers took food diaries from 722 community-dwelling adults in the UK and measured disability according to difficulty performing daily activities like moving around the house, getting in and out of a chair, shopping, walking and climbing stairs.
Progression of disability, followed up 18 months, 3 and 5 years later, fell into four distinct categories, from very low to severe.
Results showed that adults who ate more protein were less likely to become disabled over the 5-year follow-up than those with lower protein intake, after factoring in gender, education, physical activity, cognition and chronic diseases.
Lead author of the study, Dr Nuno Mendonca, told Nutrition Insight, “We believe that the largest benefit of protein consumption is due to delaying muscle mass and strength loss.”
Protein is critical for maintaining lean muscle mass, needed for strength and mobility, and healthy bone density. Not only that, if protein stores are low, the liver will draw on the muscle’s protein stores to maintain energy levels between meals.
Dietary protein also has a multitude of other important bodily functions including formation of enzymes and hormones, transporting molecules through the bloodstream, manufacturing antibodies and regulating acid-alkaline levels.
Adults in the study who consumed 1g protein per kg of body weight each day were more likely to have lower disability, supporting calls to increase recommended protein intakes.
For a 58 kg person, that could easily be met by eating 2 eggs for breakfast, 100g yoghurt with lunch and a 100g serve of salmon for dinner – all soft foods for people with dentition or swallowing difficulties.
For adults with poor appetite, eating small meals with protein shakes for morning and afternoon tea will help boost protein intake.
It’s important to note that protein needs increase when the body is stressed by infection, burns, cancer or injury.
And to maximise muscle mass and strength, the benefits of regular physical activity in conjunction with protein intake cannot be underestimated.
Protein, an indispensable part of our diet, has multiple roles in the body – particularly in aging for growth, repair and maintaining muscle mass. But dietary proteins are not all equal. Here are some nuts and bolts of this exquisitely complex nutrient.
Protein, carbohydrate and fat are all macronutrients formed by different ratios of carbon, hydrogen and oxygen. Additionally, protein contains nitrogen.
Proteins come in all shapes and sizes. They are created from twenty amino acids joined in fifty to tens of thousands of different combinations to make enzymes, antibodies and hormones, transport molecules and regulate the body’s acid-alkaline balance.
Nine amino acids are essential – the body cannot make them, so they must come from dietary sources. These are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Six amino acids are conditionally essential (needed in special circumstances like illness) and five are dispensable as the body can synthesise plenty of them.
The biological activity and nutritional benefits of protein vary according to how the amino acids are configured and how the body digests them. Based on this, various methods have been devised to measure protein quality – availability of its amino acids – and digestibility – how the protein is best used.
The biological value (BV) scoring system assumes that protein is the only dietary source of nitrogen. It measures protein quality by calculating a ratio of how much nitrogen is absorbed versus the amount excreted then multiplied by 100 to give a percentage of nitrogen used by the body.
The protein digestibility-corrected amino-acid score (PDCAAS) ranks protein quality by comparing its amino acid profile with a reference score, corrected for faecal nitrogen digestibility. This score was backed jointly by the Food and Agricultural and World Health Organisations (FAO/WHO) in 1989 as the best way to assess protein quality.
But the PDAAS has limitations; for instance measuring amino acid synthesis in the small intestine would be a better assessment of their digestion than in the large bowel (colon). Further analysis has suggested that the PDCAAS tends to underestimate high-quality proteins and overestimate low-quality proteins.
The FAO now recommends the digestible indispensable amino acid score (DIAAS), which measures the digestibility of individual amino acids at the end of the small intestine and may therefore be more accurate.
Despite some variation, the quality ratings generally agree on high protein food sources. Animal protein contains all the essential amino acids and is therefore complete. Eggs and dairy protein are ranked as high-quality proteins, followed by meat, chicken and fish. Eggs and dairy are easily digested and are good options for people with digestive disorders.
Vegetable protein typically lacks one or more amino acids. But the following combinations provide all essential amino acids and are therefore highly ranked: rice and peas; grains and legumes; grains and vegetables; grains, nuts and seeds; legumes, nuts and seeds. Importantly, the body doesn’t necessarily need all amino acids in one meal – they can be spread out over the day.
Some vegetable proteins do contain all essential amino acids. This includes hempseed, pea protein and quinoa.
This is good news in light of mounting research showing the superior health benefits of a plant-based diet. Plant foods provide fibre and nature’s medicinal cabinet of vitamins, minerals and phytonutrients. Concerns over ethics of animal farming and environmental sustainability are also driving a growing demand for diets higher in plant foods.