Obesity and Fructose Metabolism

Obesity & Lifestyle Counselling

• Obesity and sedentary lifestyles increase the risk of NAFLD.
• Nutritional and lifestyle counselling are essential interventions to manage NAFLD.

Fructose Metabolism

• Galactose is a common constituent of glycolipids and glycoproteins.
• Fructose metabolism is unregulated, meaning its transport and metabolism do not require insulin.
• Liver, intestines, kidneys, adipose tissue, and muscle tissue are capable of metabolizing fructose.
• The majority of fructose is transported to and metabolized by the liver, where it is converted into glycogen or TAGs.
• Fructose absorption is passive and facilitated by GLUT 5 transporters.
• A high fructose diet increases absorption by upregulating additional transport mechanisms.
• Excess fructose metabolites can lead to various metabolic pathways, including fatty acid synthesis and cholesterol synthesis.

Dietary Considerations

• Indigestible polysaccharides are known as dietary fiber.
• The Mediterranean diet is recommended for preventing and treating NAFLD.

Weight Management

• Reducing body weight by 5-10% can improve overall health.

Medications Associated with Weight Gain

• Antidepressants, especially TCAs, antipsychotics, corticosteroids, antihyperglycemic drugs, and lithium are associated with weight gain.
• Antipsychotics can cause a significant weight gain of 9–12 kg, along with insulin resistance changes.
• Lithium (treats mania) can cause weight gain of 10 kg or more.

Appetite Suppressants

• Bupropion, alone or in combination with naltrexone, can be used as appetite suppressants.

Bupropion

• Sympathomimetic (stimulant-like) drug used for antidepressant, smoking cessation aid, and appetite suppression.
• Adverse effects include dry mouth, constipation, agitation, insomnia, anxiety, and rarely, seizures (contraindicated in those with seizure history).

Bupropion + Naltrexone

• Adverse effects include nausea & vomiting, constipation, headache, dizziness, insomnia, and dry mouth.
• Contraindicated with concurrent opioid therapy due to the risk of precipitating opioid withdrawal.
• Suppresses appetite by mediating hormones involved in appetite and reward.

Orlistat

• Lipase inhibitor.
• Inhibits pancreatic and gastric lipase, reducing intestinal dietary fat absorption by 30%.
• Adverse effects include oily spotting, flatus with discharge, fecal urgency, and decreased absorption of fat-soluble vitamins.
• Contraindicated in patients with chronic malabsorption syndrome or cholestasis.

Incretin Hormones

• GLP-1 and GIP are the two main incretin hormones responsible for glucose-induced insulin secretion.

Role of GLP-1

• Increases satiety, decreases gastric emptying, and affects reward-related systems in the brain.

Role of GIP

• Delays gastric emptying and plays a role in glucose homeostasis.

This quiz covers the relationship between obesity, lifestyle counselling, and fructose metabolism. It addresses key aspects such as the risks of non-alcoholic fatty liver disease (NAFLD) and the metabolic pathways affected by high fructose intake. Explore how dietary considerations and interventions can impact overall health.