Food is the most basic item on the human hierarchy of needs and his survival depends on this. His ability to meet this need ties so strongly with his ability to realize his full potentials and live a life of dignity. This is aptly demonstrated in the Sustainable Development Goal 2, known as the ‘’zero hunger’’ goal and has strong interconnection and reinforcing effects on the sixteen other goals.
This goal states as follows: “to end hunger, achieve food security and improved nutrition and promote sustainable agriculture”. The interest of this paper to examine how the socio-economic dimension of protein deficiency in Nigerian diets relates strongly to this goal.
Protein and its significance
Protein is a macronutrient and represents one of the major food classes, which make up a balanced diet. It is made up of smaller units called amino acids, which are attached together in a long chain. It is important for growth and maintenance of the human body (Herman, 2019). It also performs regulatory and catalytic functions, protecting against infection and serving as a source of energy (King et al, 2015).
Protein availability in foods
Protein occurs in a wide range of foods such as meat, dairy, eggs, fish, soybeans, cowpea, whole grains, cereals, etc. (Young and Pellet, 1994). Proteins from plant-baseds food are cheaper than those from animal-based sources. It is important to note that the body also synthesizes amino acids but cannot produce the following nine essential amino acids which have to be made available through diet, namely: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and violine (Vries-ten Have 2020).
The National Protein Deficiency Report (2019) indicated that the majority of food consumed in Nigeria are plant-based staples and nutritional analyses reveal that they are low in protein quality and mostly lack essential amino acids such as methionine and lysine that can be produced mainly from animal source proteins, with the exception of soya beans, a plant-based source. Vries-ten Have (2020) shows that about 40 per cent of the Nigerian population eats beef frequently, eggs and chicken are eaten frequently by 25 per cent while milk was frequently consumed by one-third of the population.
Protein deficiency and its effects
The human body needs to consume sufficient amounts of protein on a daily basis. More importantly, the protein consumption must be adequate in both the quantity and quality of its amino acid to enable the body get all the required essential amino acids (Vries-ten Have 2020).
Nutrition experts recommend at least an intake of 0.8g/kg body weight/day as this will safely and adequately meet the protein requirement of most healthy persons.
This is referred to as the Recommended Dietary Allowance (RDA). A situation where an individual fails to meet up with this nutrition threshold is termed protein deficiency. From another technical perspective, it relates to a situation where the human body is deficient in one or more of the essential amino acids.
Nigeria is one of the developing countries combating low intake of protein and this has resulted in nutritional deficiency among all age groups. Its symptoms are chronic fatigue, retarded growth and development in children and adults, slow wound healing and decreased resistance to infections, among others.
Ubesie et al., 2012, corroborated this, stating that the burden of protein malnutrition in Nigeria is high and it is associated with severe forms of disease conditions and high level of mortality. Other striking findings from other studies include that of Akerele et al (2017) that also confirmed that a substantial portion of households in Nigeria suffered deficiency of protein and other micronutrients.
Hamidu et al., (2010) in a study in Maiduguri, North-Eastern Nigeria, indicated that children had more infections associated with protein deficiency, which included: marasmus, malaria, pneumonia and measles, while kwashiorkor was recorded as the highest. The study stated emphatically that protein deficiency was high among children below five years of age.
Socio-economic and development perspectives of protein deficiency
In Nigeria, the most crucial determinant of protein consumption adequacy in terms of quantity and quality is the socio-economic class of the population. Higher income earners, more than low-income earners, on the average, consume a wider variety of protein foods comprising a good mix of animal and plant-based foods.
This is confirmed by the Nigerian Protein Deficiency Report which affirmed that 51.0 per cent of respondents surveyed did not consume protein-rich food, mainly due to high cost.
The report confirmed further that the driving force for food consumed are availability (91.0 per cent) and affordability (68.0 per cent). Vries-ten Have (2020) confirmed this position, stating that protein-rich foods are usually expensive and that not all households have the purchasing power to acquire them.
Closely linked with Protein malnutrition is the issue of poverty. The Nigerian National Bureau of Statistics in its poverty and inequality report from September 2018 to October 2019 stated that 40.0 per cent of Nigerians live below the poverty line of N137,430.00 ($381.75 and about $366.48 in September 2020 Naira value using a Naira depreciation of 14 per cent) per year, representing 82.9 million people out of a population of 200 million.
Coupled with the losses or reduced household incomes occasioned by the recent COVID-19 pandemic, this suggests that the essential and more costly protein-based foods will get further beyond the reach of Nigerians. The scenario could better be imagined in the rural areas, with a poverty level of 47.0 per cent, according to Awotide et al., (2010).
From the Public Health point of view, insufficient protein intake is generally high among under-five children, adolescent girls and women of reproductive age. Particularly, protein deficiency is the cause of stunting (low weight for height) and wasting (low height for age).
According to the Multiple Cluster Survey (2017), no improvement was recorded in the nutritional status of Nigerians during 2007-2016 as underweight and stunting increased. Underweight moved from 25 per cent to 32 per cent and stunting from 34.5 per cent to 43.6 per cent, while the prevalence of wasting among under 5 years children remained at a national average of 10.8 per cent. It must also be noted as well that low protein intake was observed among the elderly.
On the global level, nutrition deficiency is best captured by individual country performance on the Global Hunger Index (GHI). It has four main indicators, which describe country performances, and these are: undernourishment, child stunting, child wasting, and child mortality. The GHI scale ranges from 0-100, with 0 being a state of no hunger and 100 being the worst status of hunger (Von et al., 2019).
The GHI has witnessed successive decline since 2000 with a fall from 29.0 to 20.0 in 2019 and indicated that the level of hunger and under-nutrition worldwide fell within the boundary of moderate to serious categories. Nigeria, with a score of 27.9 falls in the serious category and ranks 93 out of the 117 countries considered in the report.
The country-specific report shows that the GHI has successively declined in similar manner with the global trend since 2000, while the proportion of the population that is undernourished has increased slowly from 6.2 per cent to over 13.4 per cent between 2010 to 2019, which confirms that more people are getting more hungry, year after year.
The global economic cost of malnutrition is estimated at 2 to 3 per cent of Gross Domestic Product. However, it is estimated at 11 per cent in Nigeria, according to a UNICEF report (Vanguard newspaper, 2020)
Finally, focusing on efficiency of protein availability from different food sources and utilization by the body using the Digestible Indispensable Amino Acid Score (DIAAS) metric, Vries-ten Have (2020) concluded that foods with high protein quality (DIAAS ≥ 100) are important to bridge the nutritional gaps created by consumption of the low-quality plant-based stable foods, which on average have a DIASS of 61.
These include foods such as dairy products, beef, chicken, and eggs, which are excellent protein sources, providing DIASS ≥ 100, and which will be important in bridging the gap between lack of lysine from cereal and legumes.
Additionally, soybeans, a plant-based, food protein source that is cheaper than most animal-based protein food sources and can help bridge the lysine gap is highly recommended for consumption by Nigerians.
Adetunji Lawrence Kehinde is a Professor of Agricultural Economics, College of Agriculture, Osun State University, Osun State, Nigeria.