DIET 311

What is the diagnostic fasting blood glucose threshold for Diabetes Mellitus?

>=7.0

Why are diabetic patients at increased risk of infection?

Neuropathy impairs early detection of wounds, angiopathy causes tissue hypoxia, high glucose promotes pathogen growth, and WBC function is impaired

Which macrovascular complication of DM can lead to gangrene and amputation?

Peripheral vascular disease

Which enzyme is responsible for hydrolyzing the disaccharide sucrose into fructose and glucose?

Saccharase

Glycogenosis (glycogen storage disease) is an autosomal dominant condition.

False

Polyuria in diabetes mellitus occurs because glucose in the urine exerts an osmotic effect, pulling water into the urine.

True

Which of the following is a primary cause of diabetic NEUROPATHY?

Vascular damage to vessels supplying nerves, sorbitol accumulation, and non-enzymatic protein glycation

In diabetic RETINOPATHY, what is the final consequence of progressive microvascular changes?

Blindness from retinal ischemia, hemorrhages, and scar formation

Which type of DM classification applies when glucose intolerance FIRST appears during pregnancy?

Gestational DM

Which of the following BEST describes Metabolic Syndrome X?

Insulin resistance, compensatory hyperinsulinemia, visceral obesity, dyslipidemia, and hypertension

In disaccharidase deficiency, diarrhea occurs because undigested sugars increase osmotic activity in the intestinal lumen.

True

Lactase deficiency is rare among African-American and Asian populations.

False

In Type 1 DM, insulin resistance is a common finding.

False

Von Gierke's Disease (Hepatorenal Glycogenosis) is caused by a deficiency of which enzyme?

Glucose-6-phosphatase

A patient with DM complains of excessive hunger despite eating. Which symptom is this and what is its mechanism?

Polyphagia — cellular starvation due to depletion of carbohydrate, fat, and protein stores

Carbohydrates are digested and absorbed mainly as monosaccharides in the stomach, duodenum, and proximal jejunum.

True

What are some disorders of carbohydrates absorption

Disaccharidase deficiency

Monosaccharide malabsorption

Lactase deficiency (lactose Intolerance)

Glycogen storage deficiency (glycogenosis)

What is disaccharidase deficiency and what happens during the deficiency?

It is the lack of enzymes to break down disaccharide.

During the deficiency;

Disaccharides are not broken down

They remain in the small intestine and cause rise in osmotic pressure

This pulls water into the small intestine and causes diarrhea

Causes of the production of acid in the colon during disaccharidase deficiency

Bloating

Abdominal cramps

Acidic stools

Explosive diarrhea

What are the 2 main causes of lactase deficiency

Primary cause (genetic)

Secondary cause (damage to intestine)

What are some diseases that could cause damage to the small intestine and result in lactase deficiency

Celiac disease

Ulcerative colitis

Infections

Cystic fibriosis

Kwashiorkor

Giardiasis

What is monosaccharide malabsorption

Is the low absorption of glucose and galactose

(Symptoms same as disaccaridase deficiency)

Effects of glycogen storage diseases

Hypoglycemia

Hyperlipidemia

Ketonemia

What is diabetes mellitus (DM)

It is a chronic metabolic disorder due to the lack of insulin

The main organ blood glucose regulation takes place is?

Liver

State the hormones needed for

a) Increase in glucose

b) Decrease in glucose

a)Glucagon/GH/Epineprine/Cortisol

b)Insulin

Mention the types of diabete

Type 1 diabetes (destruction of pancreatic B cells+insulin deficiency)

Type 2 diabetes (insulin resistance+relative insulin deficiency)

Drugs/infections

Genetic defects

Pancreatic diseases

Gestational diabetes (occurs during pregnancy)

Pre-diabetes (high risk of getting diabetes)

What is the diagnostic criteria for gestational diabetes

Fasting glucose <6.1mmol/L and 2 hour OGTT <7.8mmol/L

Diagnostic criteria for diabetes

Symptoms + glucose >_ 11.1mmol/L

Fasting glucose >_7.0mmol/L

2 hour OGTT >_11.1mmol/L

Diagnostic criteria for pre-diabetes

Impaired fasting glucose 6.1-7.0mmol/L

Impaired glucose tolerance 7.8-11.1mmol/L

Causes of insulin resistance

Autoimmune antibodies

Receptor defects

Signal transmission problems

Symptoms of diabetes

Hyperglycemia

Glycosuria

Polyuria

Polydipsia

Polyphagia

Weight loss

Fatigue

What are the TWO main categories of complications of diabetes

Acute complications

Chronic complications

What are the 3 complications under acite complications

Hypoglycemia

Diabetic ketoacidosis

Hyperosmolar hyperglycemic state

Some conditions under chronic complications of diabetes

Infections

Neuropathy

Microvascular diseases

Macrovascular diseases

What is HbA1c?

The proportion of haemoglobin with glucose stuck to it

Type 1 diabetes cannot be prevented but type 2 diabetes can

True

What is the treatment for type 1 and 2 diabetes

Type 1-Insulin

Type 2-Lifestyle changes/insulin

The male sex hormone testosterone decreases metabolic rate by reducing skeletal muscle mass.

False

Indirect calorimetry calculates metabolic rate based on the rate of oxygen utilization, since over 95% of energy expended is derived from oxygen reactions.

True

Where does anaerobic glucose metabolism (glycolysis) take place in the cell?

Cytoplasm

What is the 'energy currency' of metabolism used to energize all cellular functions?

Adenosine Triphosphate (ATP)

BMR falls about 10% during sleep and up to 40% during prolonged starvation.

True

In the respiratory quotient (RQ), which fuel substrate has an RQ of 1.00?

Carbohydrates

A high-protein meal raises metabolic rate by approximately how much, and for how long?

30%, lasting 3–12 hours

What percentage of daily energy expenditure does BMR typically account for in sedentary individuals?

50-70%

How much can a trained athlete increase their metabolic rate during exercise?

20-fold

Protein produces the same amount of energy when oxidized in the body as it does in a bomb calorimeter.

False

In nutrition, one Kilocalorie equals __________ gram calories.

1000

Phosphocreatine can be used directly by cells as an energy source without conversion.

False

Which nutrient contains the most chemical energy per unit weight due to its high carbon and hydrogen content?

Fat

Which method of measuring metabolic rate measures heat directly released from the body using a specially constructed chamber?

Direct calorimetry

The BMR is measured after a fast of at least __________ hours.

12

What is metabolism

Refers to all the chemical reactions and energy changes in the body’s cells