Biofortification: Introduction, Approaches, Limitations, and Challenges

Abstract

Micronutrient malnutrition is known to affect more than half of the world’s population and considered to be among the most serious global challenges to humankind. Modern plant breeding has been historically oriented toward achieving high agronomic yields rather than nutritional quality, and other efforts related to alleviating the problem have been primarily through industrial fortification or pharmaceutical supplementation. Micronutrient malnutrition or the hidden hunger is very common among women and preschool children caused mainly by low dietary intake of micronutrients, especially Zn and Fe. Biofortification, the process of increasing the bioavailable concentrations of essential elements in edible portions of crop plants through agronomic intervention or genetic selection, may be the solution to malnutrition or hidden hunger mitigation. The Consultative Group on International Agricultural Research has been investigating the genetic potential to increase bioavailable Fe and Zn in staple food crops such as rice, wheat, maize, common beans, and cassava.

Glossary

Anemia

condition in which the number of red blood cells or their oxygen-carrying capacity is insufficient to meet physiological needs. The number of red blood cells is dependent on age, gender, and altitude and is altered by smoking, or during pregnancy the hemoglobin threshold used to define anemia is <11 g/dL

Antinutrient

a substance that impairs the absorption of an essential element by the gut

Bioavailability

measure of fractional utilization of orally ingested nutrient and also defined as the proportion of a particular nutrient that can be used by the body to provide its associated biological function. In simple words it is the amount of an element in a food constituent or a meal that can be absorbed and used by a person eating the meal. Bioavailability also refers to the portion of an ingested nutrient that can be absorbed in the human gut. The bioavailability of minerals can be reduced or enhanced by the consumption of food rich in antinutrients (inhibitors of absorption) or nutritional enhancers, respectively

Biofortification

process for improving the nutritional value of the edible parts of the plants, through mineral fertilization, conventional breeding, or transgenic approaches. It can also be defined as the process of increasing the bioavailable concentrations of an element in edible portions of crop plants through agronomic intervention or genetic approaches

Disability-adjusted life year (DALY)

a time-based parameter for assessing global burden of disease that combines years of life lost due to premature mortality (years of life lost, YLL) and years of life lost due to time lived in states of less than full health (years lived with disability, YLD): DALY = YLL + YLD

Hidden hunger

the term “hidden hunger” has been used to describe the micronutrient malnutrition inherent in human diets that are adequate in calories but lack vitamins and/or mineral elements

Hunger

the physical sensation of desiring food. When politicians, relief workers, and social scientists talk about people suffering from hunger, they usually refer to those who, for sustained periods, are unable to eat sufficient food to meet basic nutritional needs

Food fortification with iron

a way to increase iron concentration in food by adding an iron compound (e.g., ferrous sulfate heptahydrate, ferrous gluconate, and sodium FeEDTA among others) to processed food (e.g., infant formula or cereals, wheat flour products, and corn meal among others)

Fortification

the addition of an ingredient to food to increase the concentration of a particular element

Malnutrition

the condition that results from eating a diet in which certain nutrients are lacking, in excess (too high in intake), or in the wrong proportions. The verb form is “malnourish”; “malnourishment” is sometimes used instead of “malnutrition.” A number of different nutrition disorders may arise, depending on which nutrients are under- or overabundant in the diet. In most of the world, malnutrition is present in the form of undernutrition, which is caused by a diet lacking adequate calories and protein and not enough food, and of poor quality. Extreme undernourishment is starvation, and its symptoms and effects are inanition. While malnutrition is more common in less developed countries, it is also present in industrialized countries. In wealthier nations it is more likely to be caused by unhealthy diets with excess energy, fats, and refined carbohydrates (WHO 2001)

Promoter

a substance that stimulates the absorption of an essential element by the gut

Reference nutrient intake (RNI)

the amount of an element that is enough, or more than enough, for most people in a group (usually at least 97 %). If the average intake of a group is at the RNI level, then the risk of deficiency in the group is small

Regulators

organic compounds, either natural or synthetic, are able to modify or control plant growth and/or development. Also, plant growth regulators (PGRs)

Supplementation

the addition of an element to the diet to make up for an insufficiency