Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!

Chapter 10. Nutritional Diseases

Essential Nutrients

An adequate diet must provide sufficient total proteins, sufficient total calories, essential amino acids, essential fatty acids, vitamins, and minerals. A deficiency of any of these dietary factors leads to disordered cellular metabolism and cellular injury with recognizable symptoms and signs of nutritional deficiency. Nutritional diseases arising from total protein-energy deficiency and various vitamin and mineral deficiencies are well-recognized (Table 10-1).

Table 10–1. Principal Human Nutrients and Disorders Resulting from Nutritional Deficiency or Excess.
View Table||Download (.pdf)
Table 10–1. Principal Human Nutrients and Disorders Resulting from Nutritional Deficiency or Excess.
Nutrient Physiologic Importance Deficiency Excess
Protein Numerous. Marasmus; kwashiorkor; growth retardation. None.
Calories Numerous. Marasmus; kwashiorkor; growth retardation. Obesity.
Fat-soluble vitamins 1
Vitamin A Retinol is constituent of retinal rod pigment rhodopsin. Maintain epithelia. Loss of night vision; increased thickness of squamous epithelia; Bitot's spots; xerophthalmia, keratomalacia (eyes); follicular hyperkeratosis (skin). Bleeding; hepatosplenomegaly 2 (rare).
Vitamin D (cholecalciferol) 1,25-Dihydroxycholecalciferol activates calcium absorption in intestine and causes bone mineralization. Rickets (children); osteomalacia (adults). Hypercalcemia leading to metastatic calcification and renal damage 2 (rare).
Vitamin K Required for synthesis of prothrombin and clotting factors, VII, IX, and X. Hypoprothrombinemia resulting in bleeding tendency. Hemolytic anemia 2 (rare).
Water-soluble vitamins 1
Vitamin C (ascorbic acid) Required for synthesis of collagen and osteoid. Scurvy; impaired wound healing. Minimal—possibly urinary calculi.
Thiamine (vitamin B 1 ) Coenzyme in decarboxylase systems; required for synthesis of acetylcholine. Beriberi (wet and dry); Wernicke's encephalopathy; Korsakoff's syndrome. Transient flushing, dizziness.
Riboflavin (vitamin B 2 ) Constituent of flavoproteins. Cheilosis, glossitis, angular stomatitis; corneal vascularization. None.
Niacin Constituent of NAD and NADP. Pellagra. Flushing due to vasodilation occurs with intravenous injection (rare).
Pyridoxine (vitamin B 6 ) Coenzyme for decarboxylase and transaminase systems. Glossitis; blepharitis; dermatitis; cheilosis; peripheral neuropathy; sideroblastic anemia. Transient paresthesias.
Folic acid Required for nucleic acid synthesis. Megaloblastic anemia. None.
Vitamin B 12 Required for nucleic acid synthesis. Megaloblastic anemia; subacute combined degeneration of spinal cord; peripheral neuropathy. None.
Minerals
Iron Constituent of hemoglobin and myoglobin. Hypochromic anemia; loss of mucosal integrity. Hemochromatosis.

1 The fat-soluble vitamins are present especially in fatty foods (milk, butter, etc) and may be deficient when there is fat malabsorption for any reason. Water-soluble vitamins are widely distributed in fruits, vegetables, and animal products, with the exception of vitamin B 12 , which is found almost exclusively in meat. Water-soluble vitamins are less affected by generalized malabsorption states; specific malabsorption of vitamin B 12 occurs in pernicious anemia.

2 Note that excess amounts of fat-soluble vitamins accumulate in body fat stores and may lead to toxicity; toxicity of water-soluble vitamins is much rarer, probably because of rapid excretion of any excess in the urine.

Nutritional Deficiency

Deficiency of an essential nutrient may arise in a variety of ways.

Primary Nutritional ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.

This site uses cookies to provide, maintain and improve your experience. MH Privacy Center Close