PRIMARY DISEASES OF NUTRITION INADEQUACY AND EXCESS

DR PATRICIA ESEIGBE MBBS, MPH(Liverpool), FWACP

LECTURER/CONSULTANT

DEPARTMENT OF FAMILY MEDICINE

BINGHAM UNIVERSITY/ BINGHAM UNIVERSITY TEACHING HOSPITAL, JOS.

FEBRUARY 2024.

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OUTLINE

OBJECTIVES

INTRODUCTION

Introduction -2

• Macronutrients are Carbohydrates, Proteins (including essential amino acids), Fats (including essential fatty acids), Macro-minerals, and Water.
• Macro-minerals are Na, Cl, K, Ca, P, and Mg
• Micronutrients are Vitamins and Minerals
• Water-soluble vitamins are Vitamin C and B
• Fat-soluble vitamins are Vitamins A, D, E, and K
• Essential trace minerals are Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Selenium, and Zinc.
• All trace minerals are toxic at high levels.
• Lack of nutrients can result in deficiency syndromes
• Excess intake of macronutrients can lead to obesity and related disorders
• Excess intake of micronutrients can be toxic.

NUTRITIONAL REQUIREMENTS

• Good nutrition aims to achieve and maintain a desirable body composition and high potential for physical and mental work.
• Balancing energy intake with energy expenditure is necessary for a desirable body weight.
• Energy expenditure depends on age, sex, weight, and metabolic and physical activity
• If energy intake exceeds expenditure, weight is gained.
• If energy intake is less than expenditure, weight is lost.
• Daily dietary requirements for essential nutrients also depend on age, sex, weight, and metabolic and physical activity.
• Pregnant women and infants have special nutritional needs.
• Generally, the recommended intake decreases with ageing because physical activity tends to decrease, resulting in less energy expended.

Nutritional requirements -2

The new Food Guide Pyramid emphasizes the following

• Increasing consumption of whole grains
• Increasing consumption of vegetables and fruits
• Substituting fat-free or low-fat milk products for whole-fat milk products
• Reducing consumption of saturated fats and trans fatty acids
• Exercising regularly
• Adequate fluid (water) intake

Fats should constitute ≤ 30% of total calories, and saturated and trans fatty acids should constitute 10%.

Routine use of nutritional supplements is not necessary/beneficial, some supplements can be harmful.

MALNUTRITION

• Malnutrition includes undernutrition and over-nutrition.
• Undernutrition can result from inadequate ingestion of nutrients, malabsorption, impaired metabolism, loss of nutrients due to diarrhoea, or increased nutritional requirements.
• Primary nutrient deficiency is due to inadequate nutrient intake while the other causes result in Secondary nutrient deficiency.
• Undernutrition is associated with many disorders and circumstances, including poverty and social deprivation.
• The risk of undernutrition is greater at certain times, such as during infancy, early childhood, adolescence, pregnancy, breastfeeding, and old age.

PROTEIN ENERGY UNDERNUTRITION

• Protein-energy undernutrition (PEU) is an energy deficit
• Primary PEU often occurs in children and the elderly
• It is due to chronic deficiency of all macronutrients
• It commonly involves deficiencies of many micro-nutrients.
• It can be sudden (starvation) or gradual.
• Severity ranges from subclinical deficiencies to obvious wasting – with oedema, hair loss, and skin atrophy
• PEU often results in multiple organ system impairment
• Diagnostic is both clinical and laboratory: Marasmus, Kwashiorkor
• Treatment entails correcting fluid/electrolyte deficits and gradually replenishing nutrients.

ESSENTIAL FATTY ACID DEFICIENCY

• Essential fatty acid (EFA) deficiency is rare.
• It occurs often in infants fed diets deficient in EFAs
• EFAs linoleic and linolenic acid are substrates for the endogenous synthesis of other fatty acids that are needed for many physiologic processes; including maintaining the integrity of skin and cell membranes and synthesizing prostaglandins and leukotrienes.
• For EFA deficiency to develop, dietary intake must be very low.
• Small amounts of EFAs can prevent EFA deficiency.
• Signs of EFA deficiency include scaly dermatitis, alopecia, thrombocytopenia, and in children, growth retardation.
• Dietary replenishment of EFAs reverses the deficiency.

VITAMIN DEFICIENCY AND TOXICITY

• Fat soluble vitamins are Vitamins A, D, E, and K.
• Water soluble are Vitamins B and C
• The B vitamins include;
• Biotin
• Folate
• Niacin
• Pantothenic acid
• Thiamine (B1)
• Riboflavin (B2)
• Pyridoxine (B6)
• Cobalamins (B12)

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VITAMINS

BIOTIN AND PANTOTHENIC ACID

• Biotin acts as a coenzyme for carboxylation reactions essential to fat and carbohydrate metabolism.
• Pantothenic acid is widely distributed in foods. It is an essential component of coenzyme A.
• Isolated deficiency of biotin and pantothenic acid virtually never occurs.

FOLATE

• Folate (Folic acid) is involved in RBC maturation and synthesis of purines and pyrimidines. They are required for foetal nervous system development.
• Folate deficiency is common. It may result from inadequate intake, malabsorption, or use of some drugs.
• Deficiency of folate causes megaloblastic anaemia; including glossitis, diarrhoea, depression, confusion
• Maternal deficiency increases the risk of neural tube birth defects
• Diagnosis requires laboratory testing to confirm
• Treatment with oral folate is usually successful; 400 – 1000 micrograms daily

VITAMINS

NIACIN

• Dietary niacin deficiency causes Pellagra
• Clinical manifestations include the three Ds; i) Dermatitis (localized pigmented rash), ii) Diarrhoea (gastroenteritis), and iii) Dementia (widespread neurological deficits and cognitive decline).
• Diagnosis is usually clinical
• Dietary supplementation (oral or IM if needed) is successful in treatment. Nicotinamide may be given orally 40 – 250 mg/day in divided doses.
• Niacin (nicotinic acid) in large amounts is sometimes used to lower LDL and to increase HDL cholesterol levels. Its symptoms may be flushing, and hepatotoxicity (rare).

VITAMINS

RIBOFLAVIN (Vitamin B2)

• Riboflavin is involved in carbohydrate metabolism. It is essentially nontoxic.
• Its deficiency usually occurs with other B-vitamin deficiencies.
• Primary riboflavin deficiency results from inadequate intake of fortified cereals, milk, and other animal products.
• Secondary deficiencies are due to chronic diarrhoea, malabsorption syndromes, liver disorders, dialysis, chronic alcoholism, long-term barbiturate use
• Clinical features of deficiency are sore-throat, mouth/lip lesions, glossitis, conjunctivitis, seborrheic dermatitis, and normochromic normocytic anaemia.
• Diagnosis is usually clinical
• Treatment is oral 5-10mg riboflavin daily, or IM riboflavin sore throat

VITAMINS

THIAMIN (Vitamin B1)

• Thiamine is widely available in diets. It is involved in carbohydrate, fat, amino acid, glucose, and alcohol metabolism. It is essentially nontoxic.
• Thiamine deficiency causes Beriberi. It is most common among people subsisting on white rice or highly refined carbohydrates, and among alcoholics.
• Clinical features of deficiency are diffuse polyneuropathy, high-output heart failure, and Wernicke-Korsakoff syndrome.
• Can be Dry beriberi (stocking-glove distribution of peripheral neurologic deficits), Cardiovascular (wet) beriberi, Infantile beriberi neonates breastfed by thiamine-deficient mothers).
• Diagnosis is a favourable response to thiamine.
• Treatment is by supplemental thiamine with dose based on clinical manifestation; oral thiamine 10-20mg daily (mild), 20-30mg daily (moderate to advanced neuropathy), IV/IM 50-100mg (wet beriberi, Wernicke)

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VITAMINS

VITAMIN B6

• Includes a group of closely related compounds: pyridoxine, pyridoxal, and pyridoxamine.
• Act as a coenzyme in important reactions in blood, CNS, and skin. It is important in heme and nucleic acid biosynthesis, and in lipid, carbohydrate, and amino acid metabolism.
• Dietary deficiency is rare because vitamin B6 is present in most foods
• Clinical features of deficiency include pellagra-like syndrome
• Diagnosis is clinical
• Treatment is oral pyridoxine
• Vitamin B6 toxicity may be caused by the ingestion of mega doses (> 500mg/day) of pyridoxine. Treatment is to stop taking B6. Recovery is slow and may be incomplete.

VITAMINS

COBALAMIN (Vitamin B12)

• Cobalamin is the general term. Is involved in nucleic acid metabolism and myelin synthesis/repair. B12 stored in the liver can normally sustain physiologic needs for 3 – 5 years if B12 intake stops (vegans).
• Deficiency causes megaloblastic anaemia, damage to the white matter of the spinal cord and brain, and peripheral neuropathy.
• Diagnosis is by measuring serum vitamin B12 levels.
• Schilling test helps determine aetiology.
• Treatment consists of oral (1000-2000 micrograms daily) or parenteral vitamin B12.
• Folate should not be used instead of B12 because Folate may alleviate the anaemia but allow neurologic deficits to progress.

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VITAMINS

VITAMIN C (ASCORBIC ACID)

• Ascorbic acid plays a role in collagen, carnitine, hormone, and amino acid formation. It is essential for wound healing and facilitates recovery from burns.
• It is an antioxidant, supports immune function, and facilitates the absorption of iron.
• Vitamin C deficiency causes Scurvy.
• Primary deficiency is usually due to inadequate diet.
• The need for dietary vitamin C is increased by febrile illnesses, inflammatory disorders (particularly diarrhoeal disorders), achlorhydria, smoking, thyrotoxicosis, iron deficiency, cold or heat excess, surgery, burns, and protein deficiency.
• Heat (cooking) can destroy some vitamin C in food.
• Clinical features of deficiency include fatigue, depression, and connective tissue defects (gingivitis, petechial, rash, internal bleeding, impaired wound healing, ecchymosis, bulbar conjunctival haemorrhages). In infants and children, bone growth may be impaired.

VITAMINS

Vitamin C continued

• Treatment is a nutritious diet with supplemental ascorbic acid.
• Vitamin C deficiency is treated with oral Ascorbic acid 100 - 500mg thrice daily
• Deficiency can be prevented by giving Vitamin C 75mg daily for women and 90mg daily for men. Smokers should consume an additional 35mg. About five servings (recommended daily) of most fruits and vegetables provide > 200mg of vitamin C.
• Vitamin C toxicity – the upper limit for vitamin C intake is 2000mg/day. Toxic doses can acidify urine, cause nausea and diarrhoea, interfere with the body’s healthy antioxidant-pro-oxidant balance, and promote iron overload (in patients with thalassemia or haemochromatosis).

VITAMINS

VITAMIN A (RETINOL)

• Retinol is required for the formation of rhodopsin, a photoreceptor pigment in the retina. It also helps maintain epithelial tissues.
• Beta-carotene is converted to vitamin A.
• Vitamin A deficiency can result from inadequate intake, fat malabsorption, or liver disorders.
• Deficiency impairs immunity and haematopoiesis
• Deficiency also causes rashes and typical ocular effects – Xerophthalmia, Bitot’s spots, and Keratomalacia.
• Diagnosis is based on typical ocular findings and low serum vitamin A levels
• Treatment is either oral vitamin A or parenteral.
• Vitamin A toxicity can be acute or chronic. Can cause headaches and increased intracranial pressure. Acute toxicity also causes nausea and vomiting. Chronic toxicity can cause skin/nail changes, abnormal LFTs, and birth defects in a foetus.

VITAMINS

VITAMIN D

• Vitamin D has two main forms: ergocalciferol (D2) and cholecalciferol (D3).
• D3 is a naturally occurring form and is used for low-dose supplementation. It is synthesized in the skin by exposure to direct sunlight (ultraviolet B radiation) and obtained in the diet (fish liver oils, saltwater fish).
• Vitamin D affects many organ systems, mainly increases Ca and phosphorus absorption from the intestine and promotes normal bone formation/mineralization.
• Inadequate exposure to sunlight predisposes to vitamin D deficiency.
• Deficiency impairs bone mineralization, causing rickets in children, osteomalacia in adults, and possibly contributing to osteoporosis.
• Diagnosis – blood levels of 25 (OH0D (D2+D3), characteristic bone changes on X-ray
• Treatment is usually oral vitamin D, and if needed Ca and phosphorus
• Vitamin D toxicity usually results from taking excessive amounts. Marked hypercalcemia commonly causes symptoms – anorexia, vomiting, polyuria, polydipsia, nervousness, pruritus, renal failure. Treatment is IV hydration, corticosteroids, and bisphosphonates.

VITAMINS

VITAMIN E

• Vitamin E include tocopherols and tocotrienols. The most biologically active is α- tocopherol. They act as antioxidants
• Dietary Vitamin E deficiency occurs.
• Symptoms of deficiency are haemolytic anaemia and neurologic deficits. It may contribute to retinopathy of prematurity (retrolental fibroplasia) and intraventricular or subependymal haemorrhage in neonates.
• Diagnosis is low serum α- tocopherol or low ratio of plasma α- tocopherol to total plasma lipids
• Treatment is oral or parenteral α- tocopherol, 15-25mg/kg/day
• Vitamin E toxicity may occur in high doses, > 1000mg/day

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VITAMINS

VITAMIN K

• Vitamin K1 is phylloquinone, a dietary vitamin while K2 is menaquinone, synthesized by intestinal bacteria.
• Vitamin K is essential for coagulation
• Deficiency results from extremely inadequate intake, fat malabsorption, or use of coumarin anticoagulants.
• Neonates are prone to vitamin K deficiency
• Symptoms of deficiency include bleeding, easy bruisability, mucosal bleeding, and haemorrhagic disease of the new-born.
• Diagnosis is usually a prolonged Prothrombin Time that decreases after administration of phytonadione.
• Treatment is Phytonadione, orally or subcutaneously, 5-20mg
• Vitamin K1 is not usually toxic when taken orally. However, menadione, a synthetic water-soluble vitamin K precursor, can cause toxicity and should not be used to treat vitamin K deficiency. newborn

MINERAL DEFICIENCY AND TOXICITY

MACROMINERALS

• Six macro-minerals are required in gram amounts. There are four cations – Na, K, Ca, and Mg. And two anions – Cl and P.
• Their daily requirements range from 0.3 to 2.0g.
• Many functions like brain, bone, muscle, and heart depend on them.

MICROMINERALS

• Nine trace minerals called micro-minerals are also required in minute amounts.
• They are chromium, copper, iodine, iron, fluorine, manganese, molybdenum, selenium, and zinc.
• All trace minerals are toxic at high levels, and some are carcinogenic.

Details of each are to be discussed at an interactive session now!

NUTRITIONAL SUPPORT

• Many undernourished patients need nutritional support
• Nutritional support aims to increase lean body mass
• Oral feeding can be difficult for some patients with anorexia or with eating or absorption problems.
• Behavioural measures sometimes enhance oral intake. Such as encouraging them to eat, heating/seasoning foods, encouraging them to eat small portions, providing favourite foods, and assisting patients to eat.
• Enteral tube nutrition is indicated for patients who have a functioning gastrointestinal tract but cannot ingest enough nutrients orally.
• Parenteral nutrition is given intravenously. Can be partial or total parenteral nutrition.

OBESITY AND METABOLIC SYNDROME

OBESITY

• Obesity is excess body fat.
• Consequences of obesity depend not only on the absolute amount but also on the distribution of the fat.
• Complications include metabolic syndrome, diabetes mellitus, cardiovascular disorders, many cancers, cholelithiasis, fatty liver and cirrhosis, osteoarthritis, reproductive disorders, gastroesophageal reflux, obstructive sleep apnoea, and social and psychological problems.
• Diagnosis is based on calculating Body Mass Index (BMI), waist circumference, and sometimes body composition analysis.
• Treatment includes Nutritional management, Physical activity, Behavioural therapy, Drugs (sibutramine, orlistat), and Bariatric surgery.

OBESITY AND METABOLIC SYNDROME

METABOLIC SYNDROME

• Metabolic syndrome is also called Syndrome X or Insulin resistance syndrome
• It is characterized by a cluster of risk factors for cardiovascular disease and type 2 diabetes mellitus.
• Development of metabolic syndrome depends on the distribution as well as the amount of fat.
• Excess fat in the abdomen (called apple shape), particularly when it results in a high waist-to-hip ratio that reflects a relatively low muscle-to-fat mass ratio, increases the risk of developing metabolic syndrome.
• While it is less common among people with excess subcutaneous fat around the hips, called pear shape. And a low waist-to-hip ratio (reflecting a higher muscle-to-fat mass ratio).
• Excess abdominal fat leads to excess free fatty acids in the portal vein, increasing fat accumulation in the liver. Fat also accumulates in muscle cells. Insulin resistance develops. Glucose metabolism is impaired, and dyslipidaemia and hypertension develop. Other findings – high uric acid.

OBESITY AND METABOLIC SYNDROME

METABOLIC SYNDROME

• Metabolic syndrome has many different definitions. It is most often diagnosed when ≥ 3 of the following are present.
• Criteria often used for the diagnosis of metabolic syndrome can be seen in the next slide.

Treatment of metabolic syndrome involves;

• Healthy diet and exercise
• Metformin, sometimes
• Management of cardiovascular risk factors

RESOURCES

• Porter RS and Kaplan JL. The MERCK Manual of Diagnosis and Therapy, 19^th ed. 2011 Merck & Co. Inc. USA
• Rakel RE, Rakel DP. Textbook of Family Medicine, 9^th ed. 2016 Elsevier, Canada.

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