Problems of deficiency

Human beings have evolved in a hostile environment in which food has always been scarce. It is only in the last half-century, and only in Western Europe, North America and Australasia, that there is a surplus of food. Food is still desperately short in much of Africa, Asia and Latin America. Even without all too frequent droughts, floods and other disasters there is scarcely enough food produced world-wide to feed all the people of the world.

As shown in Figure 8.1, world food production has more than kept pace with population growth over the last four decades, so that most countries now have more food available per head of population than in the 1960s. This is total food potentially available, and does not take account of wastage and spoilage. It is noteworthy that there is still a twofold difference in food energy available per head of population between the USA (16 MJ/day) and Bangladesh (8 MJ/day).

Despite the advances in food production during the second half of the twentieth century, up to 300 million people are at risk from protein—energy malnutrition in developing countries. More importantly, as shown in Figures 8.2 and 8.3, the world population will increase from the present 6.25 billion to 8 billion by 2021, and most of this increase will be in less developed countries. It is extremely unlikely that food production can be increased to the same extent.

Deficiency of individual nutrients is also a major problem. The total amount of food may be adequate to satisfy hunger, but the quality of the diet is inadequate:

  • Vitamin A deficiency (section 11.2.4) is the single most important cause of childhood blindness in the world, with some 14 million pre-school children showing clinical signs of deficiency and 190 million people at risk of deficiency.
  • Iron deficiency anaemia affects many millions of women in both developing and developed countries (section 11.15.2.3).
  • Deficiency of iodine affects many millions of people living in upland areas over limestone soil; in some areas of central Africa, Brazil and the Himalayas more than 90% of the population may have goitre due to iodine deficiency (section 11.15.3.3). Where children are iodine deficient both in utero and post-natally, the result is severe intellectual impairment — goitrous cretinism.
  • While deficiencies of vitamin A, iron and iodine are priority targets for the World Health Organization (WHO), deficiency of vitamins Bt (section 11.6.3) and B2 (section 11.7.3) continues to be a major problem in large areas of Asia and Africa, and selenium deficiency (section 11.15.2.5) is a significant problem in large regions of China, and elsewhere.

Deficiency of other vitamins and minerals also occurs, and can be an important cause of ill-health. Sometimes this is the result of an acute exacerbation of a marginal food shortage, as in the outbreaks of the niacin deficiency disease pellagra reported in east and southern Africa during the 1980s (section 11.8.4); sometimes it is a problem

Figure 8.1 Food available per head of population in various countries, 1961 (clear bars) and the increase in 1998 (shaded areas). From United Nations Food and Agriculture Organization data.

of immigrant populations living in a new environment, where familiar foods are not readily available and foods that are available are unfamiliar.

Diabetes Sustenance

Diabetes Sustenance

Get All The Support And Guidance You Need To Be A Success At Dealing With Diabetes The Healthy Way. This Book Is One Of The Most Valuable Resources In The World When It Comes To Learning How Nutritional Supplements Can Control Sugar Levels.

Get My Free Ebook


Post a comment