Notes on diet and nutrition for the dental hygienists and dental assistants

1. Food and Nutrition Notes
For Dental Hygienists & Dental Assistants
By
Dr. Ritam Kundu. MDS (WBUHS)
Consultant Periodontist, Dr. R Ahmed Dental College & Hospital, Kolkata.

2. Why dental hygienists need to know about Diet and Nutrition?
- There is a close inter-relation between nutrition, diet & oral health. Hence, it is important to intervene if any dietary
malpractice is identified in a patient, who has reported for dental treatment.
- Healthy dentition contributes towards maintenance of a healthy nutritional status.
- The dental hygienist has a responsibility to assess, screen and deliver nutritional information as a part of their
comprehensive education and motivation in oral health promotion duty. As a team member of oral health care worker, it is
the duty and responsibility of the dental hygienist to make the patient aware of his/her existing malnutrition status, if
present. So that the patient can improve their nutritional status and can lead a better life.
- Some of the malnutrition status are reflected in the oral cavity, which can be detected by the hygienist, like iron deficiency
anaemia.
- Following any surgical or other procedure, it is the duty of the dental hygienists or assistants to inform the patient about
the post-procedural diets. A soft diet with high quality of protein (e.g milkshake, cottage cheese etc) is indicated for wound
healing.
Role of diet on oral health and disease:
1. Vitamins like A, B Complex, Vit C and Minerals like Zinc and Iron help in maintenance of the integrity of oral mucous
membrane and they promote wound healing.
2. Sweet and sticky food increases the risk of dental caries.
3. Soft and sticky diet stays on the tooth surface, especially in cervical third and interproximal areas of the teeth. This
encourages formation of biofilm and proliferation of different pathogens.
4. Fibrous food helps in cleaning of the oral cavity.
5. Malnutrition supresses the immune system and impairs the host’s response to infection.
6. There is a relationship between obesity and periodontal diseases.

3. What is food?
Anything that is eaten, drunk or absorbed for maintenance of life, growth & repair of the tissues (Nizel 1989)
What is diet?
It is the total intake of substance that furnish nourishment and/or calories to the body (P.M Randelph 1981). It can be
considered as customary amount of food and drink taken by an individual from day to day.
What is Nutrition?
The science of food and its relationship to health. It is concerned primarily with the part played by the nutrient in body
growth, development and maintenance. (W.H.O 1971).
Sum of processes involved in taking nutrients into the body and utilizing them by ingestion, digestion, absorption, transport,
utilization in cellular level and excretion of waste products. Nutrition differs from diet. In that it deals with those elements
of food that are absorbed through the intestinal tract and enter into metabolic processes in the body in the formation and
replacement of the tissue.
What is malnutrition?
Poor nourishment resulting from improper diet or some defect of metabolism that prevents the body from utilizing the
intake of food properly.

4. What is RDA (Recommended Dietary Allowance) ?
According to the American Food and Nutrition Board, RDAs are , intake of essential nutrients on a basis of scientific
knowledge, in such an amount that are adequate to meet the known nutrient needs of a healthy persons and prevent
deficiency of the nutrients.
It is categorized by age & gender
It does not include special needs, as in illness, pregnancy etc.

5. Classification of Foods:
A) Classification by origin - Plant origin and Animal origin
B) Classification by chemical composition
Organic : containing carbon
1) Proteins
2) Fats
3) Carbohydrates
4) Vitamins
Inorganic: do not contain carbon
5) Minerals (4% of body weight)
C) Classification by predominant function:
1) Body building foods: proteins milk, meat, poultry, fish
2) Energy giving foods : cereals, sugars, roots.
3) Protective foods: vegetables, fruits, milk.

6. Nutrient: A chemical substance in foods, which is needed by the body for growth and repair. It can be grouped as
Macronutrient and micronutrient
Macronutrient: energy-yielding nutrients needed in larger amounts in the diet. These are: Carbohydrate, Protein
& Fat.
In the Indian diet, they contribute to the total energy intake in the following proportions.
- Proteins 7- 15 per cent
- Fats 10- 30 per cent
- Carbohydrates 65- 80 per cent
Micronutrient: Nutrients needed in small amounts in the diet and these are not energy producing. These are
Vitamins and minerals.
Trace Nutrients: These are required in diet, in very minor amount and they are essential for different reactions in
the body. Some of the trace elements play key role in preventing dental caries. Trace elements in human dental
enamel are derived from the environment during mineralization and during and after maturation of tooth.
These are: Vanadium, Molybdenum, Lithium, Manganese, Magnesium etc

7. Carbohydrates provide the body’s primary source of fuel for heat and energy. Carbohydrates are stored in liver and muscle
as glycogen, but excess is converted into fat for storage.
Carbohydrates contain carbon, hydrogen and oxygen with the formula Cn(H2O)n. The term is applied because the hydrogen
and oxygen are in the proportion to form water (hydrates).
Carbohydrates can be classified as follows:
■ Sugars: This can be subdivided into monosaccharides and disaccharides.
■ Polysaccharides: do not have the crystalline form of sugar, and are used in the human diet as a source of starch and
roughage.
Carbohydrates

8. Functions:
 Helps in achieving rapid energy requirement
 They provide 3.75 kcal of energy per gram.
 Synthesis of ground substance of connective tissues and some of the non essential amino
acids.
 Glucose is essential for erythrocyte and brain function.
Effects on Oral Health:
1. Dental caries is a local phenomenon caused by the diet, especially the carbohydrates. The
type, consistency, time of intake and frequency of the carbohydrates are major factors in
causation of dental caries.
2. The most important among them is Sucrose, which is utilized by the bacteria to produce
both intra and extracellular polysaccharides.
The carbohydrate reserve of a human adult is about 500gms, which is rapidly exhausted when a person is fasting.
RDA for carbohydrates is 130g/day.

9. The glycaemic index (GI):
The glycaemic index measures the rate at which glucose is absorbed through the intestine and its subsequent level in the blood.
It runs from 0 to 100. The rate at which pure glucose is absorbed and raises the blood glucose level is given a score of 100.
All other carbohydrate products are measured against this:
■ High-GI foods: 70+.
■ Medium-GI foods: 56–69.
■ Low-GI foods: <55.
High-GI foods trigger the release of insulin for the removal of excess glucose from the blood for storage as glycogen or fat. Excess
insulin is produced in response to a diet high in high-GI foods; insulin excess creates hunger pangs and the desire to overeat.
Low-GI foods are digested slowly and raise glucose level in the blood by a small amount, and hence only low levels of insulin are
produced and the body feels satisfied for longer.

10. The word ‘protein’ means “of prime importance”, because it mediates most of the actions of life. Proteins are complex
organic nitrogenous compounds. Proteins are made up of smaller units called amino acids.
Functions:
1. Formation of body tissues: skin, tendon, bone matrix, cartilages
2. Repair and maintenance of tissues
3. Synthesis of antibodies, haemoglobin, enzymes and acts as a chemical messenger in the body.
4. They provide 4 kcal of energy per gram.
RDA for protein for adults is 0.8-1 g of protein/day/kg body weight, depending upon depending on physical activity, stress,
and growth cycles
General manifestation of Protein deficiency: Kwashiorkor, Marasmus
General features:
Kwashiorkor : Stunted growth, Hepatomegaly, Anaemia , Oedema
Word Marasmus is derived from Greek word Marasmos, which means “wasting”. Affected children exhibit extreme
wasting. Old man appearance to jaws and skin and bones
Proteins

11. Oral manifestations of Protein deficiency:
1. Bright reddening of tongue
2. Loss of papillae: erythematous and smooth dorsum of tongue
3. Kwashiorkor: Edema of tongue with scalloping around the lateral margins due to indentation of the teeth.
4. Bilateral angular cheilosis
5. Fissuring of lip
6. Loss of circumoral pigmentation
7. Dry mouth
8. Decreased overall growth of jaws
9. Delayed eruption
10. Deciduous teeth may show linear hypoplasia.
Proteins should make up about 12% of the diet. To be digested, proteins have to be broken down into the constituent
amino acids. The adult human requires eight amino acids which it cannot produce or store and these are known as
essential amino acids (e.g. histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and
valine). The body can produce non-essential amino acids, but a diet of mixed proteins is recommended for health. Protein
for vegetarians is available as nuts and pulses.

12. Fats are solid at 20 degree Centigrade, they are called oils if they are liquid at that temperature. They are concentrated
sources of energy.
Classification:
Simple lipids - Triglycerides
Compound lipids- Phospholipids
Derived lipids- Cholesterol
Almost 99% of body fats are in the form of triglycerides
Functions:
1. They provide 9 kcal of energy per gram.
2. Enhances the taste of food
3. Carry the fat-soluble vitamins A, D, E & K.
4. Fat beneath skin provides insulation against cold.
5. Fat supports viscera like heart, kidney and intestine.
6. Omega-3 fats-linolenic acid-decreases cholesterol level and cardiac risk diseases by reducing blood pressure and
preventing blood clots.
Effects on oral health:
1. Phospholipids are a structural component of cell membrane, tooth enamel and dentin.
2. Research indicates that high-fat foods tend to be inhibitory towards dental caries. Small quantities of nuts and cheese
can be good between meal snacks for patients concerned with dental caries.
Lipids

13. It is a substance which must be obtained by dietary means because of a lack of capacity in the human body to
synthesize it.
Many vitamins are coenzymes which have an essential function in a chemical reaction catalyzed by a specific
enzyme.
Classification:
1. Fat-soluble: A, D, E & K
2. Water-soluble: B, C
Vitamins

16. Minerals make-up 4% of body weight.
Minerals are divided into 3 major groups.
1. Major: Calcium, Phosphate, Sodium, Potassium, Magnesium
(these are required from dietary sources in amounts greater than 100 mg per day).
2. Trace elements: Iron, Iodine, Fluorine, Zinc, Copper, Cobalt, Chromium, Manganese, Molybdenum, Selenium, Tin, Silicon,
Vanadium, Nickel
These are elements required by the body in quantities of less than a few mgs per day).
3. Trace Contaminants: with no known function: Lead, Mercury, Barium, Boron and Aluminium.
Effects on Oral health:
1. Calcium in association with vitamin D and Phosphorus is essential for proper development and maintenance of
mineralized tissues like teeth and bones.
2. Fluorides have anticaries effect on teeth.
3. Iron deficiency anemia manifests in oral cavity by pallor of oral tissues, especially the tongue.
4. Zinc deficiency can inhibit collagen formation and reduces cell-mediated immunity.
Minerals

18. Water is not formally a nutrient but additional sources of water are essential in the
diet.
As 65% of body weight is water, a 10% loss can cause metabolic problems or even
death.
The recommended daily intake is 1–2 litres and the body can only survive a few
days without water. There is increased demand in hot climates, following
strenuous exercise, in times of fever and in diarrhoea and vomiting.
The functions of water in the body are:
■ A carrier of nutrients and waste products to and from cells.
■ Helps regulate body temperature.
■ Essential to digestion and metabolism.
■ Lubricates the joints, nervous system and eyes and aids respiration.
Water

19. What is BALANCED DIET ?
It is a diet which contains varieties of food in such quantities & proportions that the need for energy, amino acids,
vitamins, fats, carbohydrates & other nutrients is adequately met for maintaining health, vitality, and general well
being & also makes provision for short duration of leanness (Chauliac 1984)
A balanced diet is one in which each nutrient from each food group in recommended servings is present for the
optimal functioning of the human.
A balanced diet contains:
Protein – 10 – 15%
Fat – 15 – 30%
Carbohydrates – remaining part
SPECIAL CONSIDERATIONS IN BALANCED DIET:
Supplementation during pregnancy : 300 kilocalories extra
During lactation: 600 kilocalories extra

21. In summary, the Food Standards Agency (FSA) states that the key to a healthy diet is to eat a variety of foods,
which for most people means eating:
■ More fruit and vegetables.
■ More bread, cereals and potatoes.
■ Less fat, sugar and salt.
■ A third of their diet made up from bread and cereals, choosing wholegrain, wholemeal, brown or ‘high fibre’ varieties
whenever possible.
■ At least five portions of fruit and vegetables every day, including fresh, frozen, tinned, dried or juiced. Fruit and vegetables
should make up about a third of food eaten each day.
■ A moderate amount of meat, fish and alternatives such as pulses, eggs, nuts and beans, choosing lower-fat versions when
possible. At least two portions of fish per week should be eaten, one of which should be oily fish.
■ Less fatty and sugary foods and drinks, such as margarine, butter, cream, chocolate and biscuits, soft drinks, sweets, jam,
cakes and ice cream.
■ Milk, cheese, yoghurt, fromage frais and other dairy products in moderate amounts, choosing lower-fat varieties
whenever possible.
■ Less salty foods.

22. Short Notes

23. The term is derived from the old English word for "twist," or "wrick,“
Rickets is caused by a deficiency in vitamin D . During growth, human bone is made and
maintained by the interaction of calcium , phosphorus , and vitamin D . Calcium is
deposited in immature bone (osteoid) in a process called calcification, which transforms
immature bone into its mature and familiar form .
Osteomalacia: it is also known as adult rickets and flat bones and diaphysis of long bones
are affected. It is most commonly seen in post menopause female with history of low
dietary calcium intake. The majority of patient have bone pain & muscle weakness.
Oral manifestation:
Teeth – developmental abnormalities of dentine & enamel.
Caries – higher risk of caries
Enamel – there may be hypoplasia of enamel, may be mottled, yellow gray in color
Treatment:
Dietary enrichment of vitamin D in the form of milk
Curative treatment includes 2000 to 4000 IU of calcium daily for 6 to 12 weeks.
Rickets

24. This disease is characterized by:
Spongy and sore gums, Loose teeth
Anemia
Swollen joint
Decreased immunocompetence
Delayed wound healing
Haemorrhage
Osteoporosis
Oral manifestations Scorbutic gingivitis: characterized by Ulcerative gingivitis and Rapid periodontal pocket
development. Finally leading to Tooth exfoliation
Scurvy

25. Fluorosis : is a cosmetic condition that affects the teeth. It’s caused by overexposure to fluoride during the first eight years of
life. This is the time when most permanent teeth are being formed.
Cause of fluorosis:
1. Excess intake of fluoride through drinking water
2. Excess use of fluoridated tablets
3. Ingestion of fluoridated toothpaste, mouth rinse
4. Use of processed foods cooked in fluoridated water
Structurally, an increase in fluoride intake results in an increase in degree and extent of porosity of the enamel. The enamel
changes described may be a result of a fluoride damage of secretory ameloblasts resulting in altered composition of enamel or
defect in maturation of enamel matrix. Such defective enamel is termed as mottled enamel.
Mottled enamel: Mottled enamel is a condition indicates the fluorosis characterized by minute white flecks, or yellow or brown
spots or areas, scattered irregularly or streaked over the surface of a tooth.
Prevention:
It’s also important to monitor the child’s use of fluoridated toothpaste. It’s important to teach the child to spit out the
toothpaste after brushing instead of swallowing it. To encourage spitting, avoid toothpastes containing flavors that children
may be likely to swallow.
Management: Cosmetic treatment.
Fluorosis

26. BMR is defined as the minimum amount of energy required by the body to maintain life at complete physical and mental rest
in the post-absorptive state (i.e. 12 hours after the last meal).
It may be noted that resting metabolic rate (RMR) is in recent use for BMR.
Several functions within the body continuously occur even at rest, such as – cardiac, respiratory, renal functions etc. for
which there is a consumption of energy. BMR measures this energy requirement at a complete rest state.
Measurement of BMR: The BMR is determined either by the apparatus of Benedict & Roth or by the Douglas bag method
Prerequisite conditions:
Post-absorptive state
Mental & physical relaxation
Person is awake
Temperature maintained at 20-25°C
Supine position.
BMR

27. BMR is expressed as cal/sq.m/hr
Adult males: 38 cal/sqm/hr
Adult females: 33 cal/sqm/hr
The average body surface area for Indian males is 1.62 sqm For females = 1.4 sqm
Surface area: BMR is directly proportional to surface area. Surface area is related to weight & height.
Sex: Men have higher (about 5%) BMR than women. Due to the higher proportion of lean muscle mass in men.
High BMR: in young, athletes and in some diseases(hyperthyroidism, HTN etc.)
Significance:
BMR is important to calculate the calorie requirement of an individual & planning of diets.
Determination of BMR is useful for the assessment of thyroid disorders.
BMR is increased in thyrotoxicosis (hyperthyroidism) and BMR is decreased in hypothyroidism.