It is recommended that 35% of the calories you consume come from protein. Protein is an essential part of a healthy diet. It provides the building blocks (amino acids) for building new body tissues and repairing worn-out tissues. Protein is also a major part of some hormones, such as insulin, which help the body in its metabolism. Proteins play important roles in bone health and cell signalling. Nevertheless, with the varied sources of protein, which one is a better choice? Animal protein or vegetal protein (protein from plant sources)?
In order for the body to efficiently utilize proteins from food, the protein must be of a high quality, containing all 9 essential amino acids in adequate amounts and is easily absorbed and used by the body. Animal proteins, because they are similar to the proteins in the human body, contain all these essential amino acids in adequate amounts. They are also more bioavailable (more readily absorbed and used). Hence, animal proteins have a high protein quality. Plant proteins, on the other hand, are deficient in some essential amino acids and are less bioavailable. Nonetheless, with the right combinations, vegetal proteins can make up for the essential amino acids they lack. But this may not make the plant proteins as bioavailable as animal proteins.
Bioavailability of minerals
Two minerals of public health concern whose bioavailability are highly influenced by their sources are iron and zinc. Iron and zinc are available in both plant and animal sources but they occur in different forms and these variety of forms affect how well humans are able to absorb and utilize them. The iron in animal sources is in a form that the body can easily absorb and use. However, iron in plant sources are in a different form from what the body is ready to absorb. This makes iron from animal sources a better choice in helping to prevent iron deficiency anaemia, a common deficiency disease.
Further, zinc is a mineral that plays important roles in controlling blood sugar levels by improving the action of insulin (a protein hormone). Plant sources often contain phytic acid which binds to the zinc in the food and reduce the human body’s ability to absorb the zinc, making zinc in plant sources less bioavailable. But, zinc in animal sources are not inhibited by any naturally-occurring component of the animal source, making zinc from animal sources more bioavailable. Thus, you will be able to meet your recommended daily amount of zinc by consuming animal sources such as meat.
Production of plant protein, over the years, has proven to be sustainable with almost no negative effect on the environment. Further, it has been shown to help reduce the concentrations of greenhouse gases in the atmosphere, consequently improving climate conditions. In fact, recent studies have shown that consuming vegetal protein is more helpful to our climate.
On the other hand, animal agriculture has been the conventional means of producing animal protein. Yet, this method of producing animal protein has had a significantly negative effect on our planet. The FAO estimates that 14.5% of human-induced greenhouse gas emissions come from animal agriculture. Of this quantity of greenhouse emissions, beef production contributes 41%, dairy farming contributes 20%, pork and poultry contribute 9% and 8% respectively. Moreover, in order to create more arable land for feed production and grazing fields for livestock rearing, many forests are cleared. This further accentuates the detrimental effect of the animal agriculture on our climate. Producing animal protein for consumption takes a great toll on our climate. Additionally, the heavy use of antibiotics in conventional production of animal protein poses a great threat to biodiversity as well as human health.
In spite of these, animal protein production can be sustainable with no harmful effect on the environment. New technologies now allow animal proteins to be produced without the slaughtering of animals or the clearing of forests to produce animal feed. Meat grown in the lab is more sustainable than meat produced by animal agriculture. Cultured meat or what has come to be known as clean meat delivers the same nutritional benefits as conventionally-produced animal protein. Moreover, cultured meat contains bioavailable nutrients and it can be used to meet specific health and nutritional needs by changing the nutrient profile to address the health or nutritional need.
In summary, both animal protein and plant protein are important, as plant sources may also provide some antioxidants. However, switching from conventionally-produced animal protein to sustainably-produced cultured meat will offer even better benefits.