The best and worst ways to get the protein you need
Improving your own health and improving the health of our planet are entirely compatible.
But you do need to know:
Which foods – and especially meats – have the highest adverse environmental impact
How to choose sustainable fish products
How to ensure you are getting the nutrition you need, whilst consuming less animal products
Because it is an ‘inconvenient truth’ that we will have to eat less animal products.
By making informed choices we can collectively reduce our diet’s associated Green House Gas (GHG) emissions and land use demand by up to 50% .
There is solid evidence that diets rich in fruits and vegetables not only reduce the risk of dementia, heart disease and cancer – but have lower carbon footprints than meat-rich ones. 
Four environmentally unfriendly facts
- Almost 50% of all antibiotics are used in the livestock sector – and 37% of all pesticides.
- 70% of all agricultural land is occupied by livestock
- 18% of current GHG emissions are generated by livestock – as much as road transport at 17.5%
- 70% of deforested land is converted to pasture. Carbon is released by this deforestation and then further increased by the livestock. A double whammy.
Analyses of a typical northern European grocery basket indicate that on average, foods with the highest environmental burden are meat products (beef, pork and poultry) and dairy products (cheese, milk and butter). 
Measures of ‘environmental impact’ generally include: associated GHGs, toxicity to humans, air pollution, effects on water eco-systems, land-use and resource depletion.
What’s the environmentally best diet?
A 2018 meta-analysis of scientific literature identified the so-called Mediterranean Diet as the best of both worlds: high nutritional scores and low carbon footprints.
On the other hand, the dietary choices identified in Northern and Western Europe, as well as in the USA, have the highest carbon footprints, relying upon dairy products as a major contribution of protein and nutrients .
The food we choose to eat is important, not only for our personal health, but for the future of our land and climate system.
So, which animal products are the most burdensome on our environment?
You don’t necessarily need to cut them out completely – although an increasing number do. But even halving the consumption of certain foods can make a huge and necessary positive impact. It is one of the easiest ways for us personally to help tackle the climate crisis.
58% of ALL the cultivated land on our planet is devoted to farming livestock – either directly for grazing or for growing animal feed.
With demand for animal protein growing rapidly as previously ‘developing’ countries move to eating more animal protein, this use of land is unsustainable in the long term.
Livestock requires all the same things we humans need to survive – land, food and water. In a populous world, these are increasingly scarce resources. If we can feed humans on less land, we will have more land to support our growing population.
Equally we will have more land to spare for rewilding, planting trees to soak up carbon – and for the conservation of natural habitats for dwindling wild populations of animals – including the insects we depend on for pollinating crops.
Beef has the lowest efficiency of resource input – it takes a lot of food, water and land for the protein you get from a cow.
In fact, we currently need to input 3kg (6-7 lb) of feed for every 450g (1 lb) of edible beef.
Beef meat also has the worst environmental impact per kg of all the common meats. Corn-fed beef tops the list of adverse impact, as corn is a chemically and mechanically intensive monoculture crop. Grass-fed is preferable in terms of land use – since well-managed grazing land can actually become a carbon sink and provide habitat in the margins.
Pork is one of our most popular meats – Europe eats about 3 times the amount of pork as it does beef. Pork does have a lower environmental burden per kg than beef, but because of its wide consumption, total pork meat production has one of the biggest negative impacts .
Pigs need just under 2kg (over 4lbs) of feed for 450g (1 lb) of edible pork.
Chicken and turkey
Generally, health research favours white meats over red meats, on the grounds that they are leaner and contain less ‘bad’ cholesterol, which is a risk factor in heart disease. The rearing of poultry produces about half of the greenhouse gases that producing the same weight of beef does .
Chickens typically need 2lbs of feed for each 1lb of edible meat.
Sheep are often grazed on hill land that would otherwise be difficult to farm for crops, and agriculturally grown feed is used far less. So, to that extent they create less of an environmental impact.
So, should you eat meat? We advise taking the middle way
– REDUCING your meat consumption, especially of beef, and buying the best possible organic, free-range meat you can afford.
Fish, especially oily fish, contain fats such as Omega-3 in good ratio with other Omega fats- making them theoretically a healthy food.
Oily fish is therefore currently recommended as part of a healthy diet. However, a reality to face when buying fish is that 90% of commercial fish stocks are dangerously overfished [4, 5].
This means fish populations are getting so small that birth rates are barely high enough to keep the population viable, let alone recover and grow.
This is particularly an issue with larger fish that are slower growing and slower to reproduce, like Cod, Tuna, Grouper, Halibut, Plaice, Salmon.
Smaller fry (like anchovies, sardines) have higher birth-rates and reach sexual maturity much younger than bigger fish, so their populations have a faster growth rate.
So, should we be buying farmed fish instead?
It’s true that fish farming has taken some of the pressure from wild populations and can be a more sustainable way to eat fish. And farmed salmon for example have a good conversion rate – almost 1:1 input feed to output edible fish.
However, there are significant negative impacts of fish farming on nearby ecosystems. The high concentration of fish in one place leads to high nutrient loads in the water – this can then encourage the growth of algal blooms that can be directly toxic to other marine animals or indirectly harmful as they starve the water below of oxygen.
We should only buy fish certified as sustainable by respected advisory bodies like the MSC (Marine Conservation Societies), and avoid fish that has been caught via destructive and non-specific techniques.
Trawling with nets that drag across the ocean floor ruins fragile eco-systems and using electromagnetic pulses will kill any organism within range. Some trawl nets are called “bulldozers of the sea” – being 3 kilometres long with mouths as wide as a rugby pitch!
Instead, try to buy line-caught or well-farmed fish. Refer to MSC’s Good Fish Guide to make a more informed consumer choice: https://www.mcsuk.org/goodfishguide/search
Locally produced eggs are relatively easy to find. Look for organic and free-range ones. These chickens will have been kept in far better conditions and will therefore be much healthier than intensively farmed ‘battery hens’.
Non-organic standards mean laying hens can be regularly fed non-specific antibiotics, that are then indirectly ingested by you. However, the European Parliament have approved restrictions on the use of antimicrobials in healthy livestock. When these new regulations come into law by 2022 – this should at least mitigate the rate at which antibiotic resistance is spreading.
DAIRY PRODUCTS (from animal milk)
The manufacture of dairy products uses a lot of water – up to 8 times that of rearing the same weight of poultry meat or of non-organic wheat cereal .
Dairy is also one of the most water-polluting forms of agriculture. The run-off from large dairy farms is causing huge issues in water systems worldwide. And we know that methane from dairy cows is a significant contributor to GHGs.
So, reducing consumption of dairy is important for the environment. But is it a good choice for your health, anyway?
The effect of dairy on your body
There is no compelling evidence to say that people who consume dairy are either more or less healthy than those who don’t.
For example, moderate dairy intake – defined as two servings a day – does not seem to increase your risk of developing cardiovascular disease or cancers .
Inflammation in body tissues is now known to be a key driver of heart disease, stroke, diabetes and some cancers. There is mixed evidence on dairy consumption and inflammation – some results show an increased presence of inflammatory biomarkers, and some a reduction . (Although one problem with research into this industry is that the majority of studies have been conducted using funding from the dairy industry, so it is hard to assure these reports are unbiased!)
In a typical western diet, dairy products currently provide 72% of the calcium requirement .
Calcium is an essential mineral, but it is commonly misconceived that we must get it from dairy milk. Green leafy vegetables such as broccoli, collards, kale, mustard greens, and bok choi, along with almonds, brazil nuts and sunflower seeds, all contain good levels of calcium.
One portion of lightly cooked kale contains approximately 120mg calcium, which is one-sixth of your daily requirements. Similarly, one portion of almonds contains 70mg or one-tenth of your RDA, so make sure you are consuming a mixture of these calcium-rich foods.
Conclusion: As long as you’re getting the micronutrients you need, it doesn’t seem to matter whether the source is animal or plant. So, a reduction in dairy, like a reduction in meat, is something we should be doing.
Will I get enough protein on a plant-based diet?
YES! Generally, diets with adequate calorific intake have adequate protein content.
Protein deficiency is not an issue in the developed world. Experts suggest that to optimise health, you need approximately 1.2–1.6g protein per kg of body weight per day. The differences depend on your age and personal activity level – with athletes possibly needing up to 2g/kg/day).
For a typical 70kg (11 stone / 154 lb) woman that’s 100g (3.6oz) of protein a day
For the typical 83kg (13 stone / 183 lb) man it’s 120g (4.2 oz) a day.
Essential amino acids making up protein
All plant foods contain at least some of the 9 essential amino acids i.e. those amino acids not synthesised by the body.
The constitution of amino acids differs between foods, however.
For example, legumes (beans, lentils, peas) are lower in methionine, and most other plant foods are lower in lysine – but as long as you consume a variety of foods, you can generally get an adequate amount of all the essential amino acids.
Current academic thinking is that the liver will store amino acids over the day, so there is no need to ‘complement’ proteins by eating them together , as was believed some years ago.
Lysine tends to be the most limited amino acid in a vegan diet, but tofu, tempeh, seitan and legumes are all good sources of lysine.
Of the amino acids, branched-chain amino acids (BCAAs) are particularly important for promoting muscle protein synthesis. These are more concentrated in animal-based protein, but still found in plant protein.
The US Food and Agriculture Organization Expert Consultation created a new system in 2011 for comparing proteins called the Digestible Indispensable Amino Acid Score (DIAAS). Comparing soy and pea protein to whey protein (from dairy milk), we find they are not far behind in their DIAAS, with soy at 0.906 and pea at 0.822 vs whey protein isolate at 1.09.
Considering this, vegans may wish to consume approximately 10% more protein to make up for the slight inferiority in plant protein digestibility.
What vitamins and minerals might I need to supplement for in a fully plant-based diet?
are the main minerals that can be deficient in a wholly vegan diet. We have already discussed how to get calcium, and vitamin B12 is now commonly enriched into many foods.
- MarmiteTM is also a great source of B vitamins, and may satisfy a desire for a ‘meaty’ saltiness.
- Iron can be found in legumes, grains, nuts and seeds: pumpkin, pistachio, sunflower, cashews, un-hulled sesame and many green vegetables.
- Whole food sources of vitamin D include mushrooms and fortified cereals
Vitamin D deficiency is very common in the winter across the whole population, however, and the NHS now advises supplementation. See https://nutrishield.com/the-products/vitamin-d/
It’s worth being aware of the fact that there are compounds in some plant foods like soy, legumes and cereals (eg. trypsin) that can inhibit the digestion of proteins and carbohydrates. These are called anti-nutritional factors . You can lessen the impact of anti-nutritional factors through specific preparations like soaking, sprouting and fermenting.
How does a vegetarian’s body compare to that of an omnivore?
Same strength. Compared to omnivorous diets, plant-based diets have no disadvantages for anaerobic or aerobic exercise performance or strength. (After all, elephants are vegans!)
Reduced risk of degenerative diseases. On the positive side, plant-based diets do typically reduce the risk of developing numerous chronic diseases over a lifespan . Vegetarians have a significantly lower risk of incidence of ischemic heart disease and of total cancer . Dementia risk is also lowered.
Lower BMI, BP, blood glucose/fats/uric acid. These positive health outcomes are likely to be caused by a vegetarian’s typically lower BMI, lower blood pressure, lower blood glucose, lower blood fats (triglycerides), and lower blood uric acid.
Fewer C-reactive proteins and lower cholesterol. In addition, vegetarians have fewer high-sensitivity C-reactive proteins (a marker of inflammation and a risk factor for cardiovascular disease) and lower ‘bad’ cholesterol levels.
An environmentally positive diet
Reducing the consumption of animal products is environmentally positive now and will become necessary in the near future. But it needs to be done mindfully to avoid any nutritional depletion .
Of course, your motives may also include reducing animal suffering – in which case you need to be well-educated in what nutrients to seek out in a pure-plant diet.
But on purely environmental and health grounds, we suggest a ‘flexitarian’ or ‘reducitarian’ approach. That is to REDUCE meat, fish and dairy consumption rather than necessarily eliminate them. So we recommend:
- Meat 0-2 times a week, minimising beef and pork.
- Oily fish 2-3 times a week, but only species that are not threatened, using fishing techniques that are non-destructive. Plant-derived Omega 3 – from eg. flax seed is a good alternative, but not quite as well absorbed as fish oil.
- Fewer than 7 eggs a week, choosing organic and local whenever possible.
- Dairy only in moderation, increasing your intake of leafy green vegetables like kale and spinach and adding a supplement that includes vitamins D and calcium. Some milk alternatives are not environmentally friendly eg. almond, so choose oat, soy and hemp milks – organic and regionally produced if possible. Mixing dairy milk and alternative milks on eg. cereals is an easy way to cut down.
Adapting your diet can be easy and delicious
Meat and two veg as a norm is off the menu – but who’s really sad about that anyway? Welcome to a culinary world of bright colours, fresh produce, warming spices and raw goodness.
There are now countless vegan meat and cheese substitutes in supermarkets that are easily incorporated into old-favourite recipes and which are perfectly satisfying.
Most of these are soy-based, so make sure you are also getting a variety of other plant and grain proteins – think of lentils, legumes (peas and beans), oats, mushrooms or even hemp.
Add a few new dishes to the repertoire that include these proteins (think curries, bakes, soups, pies, salads, stir-fries). There are plenty of resources online for nutritionally complete vegetarian or flexitarian meal plans and recipe inspirations.
In particular there is a whole free recipe book called the Health Defence Cook Book. See the recipes here: https://nutrishield.com/health-defence-cookbook-online/
We all like win-win situations, and mindful, largely plant-based eating, is a great example. Better for you (when done right), and better for the planet we love and depend upon.
After all there is no planet B!
You can download a food plan that takes all this into consideration from here. https://nutrishield.com/wp-content/uploads/2018/03/CR-News-Food-table.pdf
This article was written by Catherine Rose Biologist, Agroecologist, Creative Cook
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NutriShield is a complete health supplement that contains a high level of plant-derived nutrients, combined with vitamins and minerals, including B12, calcium, Omega 3 and vitamin D. See nutrishield.com.
Dr Paul Clayton’s best-selling book Health Defence is available from booksellers.
See online here for delicious recipes from the Health Defence Cookbook incorporating healthy foods featuring in a Mediterranean Diet.
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