A 2016 study outlined the carrying capacity of different types of food diets in the US.
Carrying capacity means the number of people that a particular type of diet that a food diet can
With the world population expected to grow through to 2050 and 2100, information like this might be of interest when considering whether the world will have enough food in the future or not, and specifically the factors that might impact food production, meeting food demand, and so on
With this in mind, we have paraphrased relevant information and numbers from the study in the guide below.
Summary – Which Type Of Food Diet Can Feed The Most People?
Which Food Diet Type Can Feed Or Support The Most Total People?
Vegetarian diets have the highest carrying capacity (with some dairy instead of meat), followed by ovo-lactarian, and then vegan diets rounding out the top three
The standard american diet, diets with more animal meats, added fats and added sweeteners, and some highly omnivorous diets tend to have lower carrying capacities
What this demonstrates is that a mainly plant based diet, with some animal based dairy included to utilize land that can’t be used for crop production, might have the highest carrying capacity compared to a completely vegan diet
Variables That May Influence The Carrying Capacity Of Different Food Diet Types
However, there are several variables and practical considerations to carrying capacity of different diets
Significant variables might be the type of land each diet type uses, and the amount of grazing land and cropland (cultivated, and perennial) that is available worldwide
Livestock can use less fertile land (grazing and pasture land) that plant based food crops generally cannot
Vegetables, fruits etc. generally need arable fertile land to be grown in large quantities
What this means is that there may be more suitable agricultural land available worldwide for livestock to graze on and use as pasture land, compared to land that can be used for certain types of crops
If we look at the study to try to get some more research data on this point, a vegetarian diet with some meat included for example may be able to provide food for more people than a purely vegan diet, because the vegan diet can’t make use of grazing land which is more abundant
So, the exact makeup/composition of the diet can impact the carrying capacity (i.e. what % of meat and animal products, and what % of plant based foods are included in the diet)
Food waste and loss, and food yields of each diet type are also important variables
For example, some plant based foods may be wasted at a higher rate at the consumer stage than some animal based food products.
Crop yield and animal feed conversion efficiency also impacts productivity at the farming stage, which impacts how effectively each food type can turn resources and inputs into output
Potential Limitations With This Study
A few potential limitations with the study are that it is based on the US only, and it also doesn’t take into account food waste of the different food groups.
What Foods Currently Feed The Most People Worldwide?
As a practical comparison to this theoretical study, you can read this guide which outlines the foods that currently feed the most people worldwide, and also what foods are the most produced worldwide.
What Might Be The Most Sustainable Individual Foods?
We’ve put together our separate guides about what the most sustainable animal meats might be, and what the most sustainable overall foods and diets might be.
Rather than carrying capacity, these guides look at other measures of sustainability like water footprint, carbon footprint, land footprint, and more.
How Many People Can Each Type Of Food Diet Feed/Support In Society?
The aggregate area available for food production was estimated to be 95 million ha cultivated cropland, 134 million ha total cropland, and 299 million ha grazing land.
Based on that assumption, the total number of people each type of food diet could support/feed would be:
– Baseline/Contemporary American Consumption Pattern Diet
402 million people, or 130% of the estimated year 2010 population
– Positive Control Diet (as per baseline except intake of fats and sweeteners is reduced to make diet energy-balanced)
421 million people, or 136% of the estimated year 2010 population
– OMNI 100 Diet (100% of person-meals follow an omnivorous healthy diet pattern)
467 million people, or 151% of the estimated year 2010 population
– OMNI 80 Diet (80% of person-meals follow an omnivorous healthy diet pattern, and 20% follow a ovo-lacto vegetarian healthy diet pattern.)
548 million people, or 178% of the estimated year 2010 population
– OMNI 60 Diet (60% of person-meals follow an omnivorous healthy diet pattern, and 40% follow a ovo-lacto vegetarian healthy diet pattern.)
669 million people, or 217% of the estimated year 2010 population
– OMNI 40 Diet (40% of person-meals follow an omnivorous healthy diet pattern, and 600% follow a ovo-lacto vegetarian healthy diet pattern.)
752 million people, or 244% of the estimated year 2010 population
– OMNI 20 (20% of person-meals follow an omnivorous healthy diet pattern, and 80% follow a ovo-lacto vegetarian healthy diet pattern.)
769 million people, or 249% of the estimated year 2010 population
– OVO Diet (Ovolacto vegetarian – Includes both eggs and dairy products.)
787 million people, or 255% of the estimated year 2010 population
– LAC (Lacto vegetarian – Includes dairy products. Excludes eggs.)
807 million people, or 261% of the estimated year 2010 population
– VEG (Vegan – Excludes all livestock products.)
735 million people, or 238% of the estimated year 2010 population
Read the full study if you want to see the full breakdown of how much of each type of land that each type of diet uses, or the food sub groups included in each type of diet.
Other Notes On The Study
The different diets use grazing land, perennial cropland and cultivated cropland in different proportions
Some diets don’t use cropland or grazing land at all
Food waste at the consumer level, and crop yields are not taken into account in the above study, and both could change the results
Another study actually finds that higher quality diets that include a lot of plant based food (fruits and vegetables) actually waste less cropland compared to lower quality processed food, sweeteners and animal feed (essentially – the “Western diet”, characterized by high intake of refined carbohydrates, added sugar, sodium, and animal products, and low intake of fruits, vegetables, and whole grains)
Diet composition (exactly what foods are included in each type of diet and in what %’s) is a big variable that could also change results
Since meat consumption is expected to increase in the future, it would be interesting to see what a diet with more animal meat protein consumption looks like from a hectares per person annually perspective, and from a carrying capacity perspective
Different diets are going to have different nutritional profiles – which may suit some, and not suit others from a health and nutrition perspective. Diets with high carrying capacities won’t work in practicality if there are associated health and nutrition inadequacies and problems with them
Newer food production methods like lab grown meat still have a land footprint, but can differ from conventional agriculture land footprints
1. Peters, C.J., Picardy, J., Darrouzet-Nardi, A.F., Wilkins, J.L., Griffin, T.S. and Fick, G.W., 2016. Carrying capacity of U.S. agricultural land: Ten diet scenarios. Elem Sci Anth, 4, p.000116. DOI: http://doi.org/10.12952/journal.elementa.000116 – https://www.elementascience.org/articles/10.12952/journal.elementa.000116/#