Fish has been an important part of the diet of humans in almost all countries in the world since the dawn of time. This feed is claimed to help prevent a range of other health problems from mental illness to blindnessThe health benefits of eating fish are being increasingly understood now. This feed is highly recommended by nutritionists. This is conjectured to be one of the major causes of reduced risk for cardiovascular diseases in Eskimos. It has been suggested that the longer lifespan of Japanese and Nordic populations may be partially due to their higher consumption of fish and seafood. Fish is claimed to help prevent a range of other health problems from mental illness to blindness. The health benefits of eating fish are being increasingly understood now.
More than two billion people in the world are estimated to suffer from micronutrient deficiencies, although considerable uncertainty exists around this estimate. Poor growth in children may be a function of dietary inadequacies during early childhood (energy, protein, and micronutrients) but also may be caused by exposure to infectious diseases and prenatal nutritional inadequacies or exposures.
Fish is often described as a protein, and perhaps for this reason, the role of fish in human nutrition is often centered around its protein content. Like other animal source foods such as eggs, milk, and meat, fish has high protein quality and its digestibility exceeds 90%. Protein deficiency was once considered to be a major cause of nutritional problems globally, although interest waned in the mid 1970’s with the publication of a manuscript that questioned its importance. In recent years however, the lack of high-quality protein in the diets of young children has been raised as a potential cause of stunting, rekindling an interest in animal sourced foods.
Certain types of fatty fish are a rich source of long chain polyunsaturated omega-3 fatty acids (PUFA) including EPA and DHA. Major sources of the PUFA in many populations traditionally have been fish and fish oils, the supply of which is not sufficient to provide the recommended intake levels of these nutrients for growing human populations. Therefore, attempts have been made by the agriculture industry to “boost” omega-3 fatty acid content of other products, including milk, eggs and poultry meat. While humans have the ability to synthesize these long chain fatty acids by elongating shorter chain fatty acids such as alpha-linolenic acid (ALA), the process is believed to be inefficient. Most studies on the relationship between PUFA and health outcomes have been conducted in high income settings where overall nutritional status is presumed to be better. Poor EPA and DHA status in pregnancy has been linked to higher risk of early preterm birth (<34 weeks) and trials of omega-3 supplementation have also shown an overall benefit for this outcome in meta-analysis. Consumption of long chain omega-3 PUFA in pregnancy is also known to be linked with improved cognitive development scores. Many studies, largely conducted in high income settings have also found associations between consumption of fatty fish and/or supplementation with long chain omega-3s and reduced risk of myocardial infarction and coronary heart disease, although heterogeneity in these findings exists.
There is also increasing attention in low- and middle-income settings around the importance of fish in providing micronutrients to populations at risk of deficiency. Considerable variation may exist in the micronutrient content of fish depending on species, the environment in which they live, whether they are wild caught or farmed, and other characteristics. Of the 2000 wild caught species from the sea commonly consumed by humans, however, nutritional analysis has only been conducted in about 350, leaving significant uncertainty around the nutritional value of fish globally. Recent efforts to model the nutritional characteristics of marine fish based on ecological characteristics have enabled the estimation of nutritional value for species not yet assessed. There have also been some recent efforts to compare the micronutrient and fatty acid content of certain wild-caught vs. farmed species in countries such as Bangladesh. Although not studied extensively, findings from a study in Bangladesh, suggest that despite growing fish consumption, largely sourced from aquaculture, micronutrient intake from fish may be declining due to poorer nutritional composition of the consumed parts of farmed fish compared with wild caught fish that once formed the majority of fish consumed. These findings suggest the importance of considering feeds, farming practices, and species composition, as elements of nutrition policy in countries where consumption of farmed fish is high. In a world where nutritious and healthy food products are essential, fish and seafood represent a critical component of the global food basket.