Essential Nutrients Quiz

Vitamin B12, Folate, Iron, and Other Essential Nutrients

• Intrinsic factor-Vitamin B12 complex binds to receptor proteins in the ileum, allowing vitamin B12 absorption; only a small amount can be absorbed without intrinsic factor.
• Vitamin B12 is mainly reabsorbed rather than lost in feces; it takes years of deficient diet before symptoms of Vitamin B12 deficiency appear.
• Vitamin B12 deficiency causes an increase in homocysteine levels and macrocytic anemia, and it interferes with the maintenance of myelin, leading to neurological symptoms.
• Folic acid deficiency can be prevented even when vitamin B12 is deficient by supplemental folic acid, which is needed for DNA synthesis.
• Vitamin B6 deficiency in infants can cause abdominal distress and convulsions.
• High levels of homocysteine increase the risk of cardiovascular disease.
• Folate coenzymes are needed for DNA synthesis and metabolism of some amino acids; folate deficiency leads to an increase in homocysteine and symptoms such as anemia, poor growth, and nerve problems.
• When folate is deficient, cells in the bone marrow that develop into red blood cells cannot replicate their DNA, leading to macrocytic anemia.
• Microcytic anemia occurs when red blood cells don't have enough hemoglobin and are smaller than normal, often due to iron deficiency.
• Non-heme and heme iron have different functions in the body, and teenagers have different iron needs based on gender and age-related factors.
• Iodine is an essential component of thyroid hormones and is found in seawater, seafood, and iodized salt.
• Fluoride is important for dental health, making tooth enamel more resistant to decay; chromium deficiency may lead to impaired glucose tolerance and elevated cholesterol and triglyceride levels.

Thrifty Genotype and Obesity

• Thrifty genotype suggests certain populations may have genes that determine increased fat storage, which was advantageous during times of famine but has led to obesity and type 2 diabetes in modern environments.
• Twin studies have shown that even with excess calories, 20% of people were lean, indicating not everyone has the thrifty genotype.
• Drifty Gene hypothesis argues that the modern distribution of the obese phenotype is due to genetic drift in genes encoding the regulation system controlling an upper limit on body fatness.
• Environmental factors affect weight within the upper and lower intervention points defined by the risk of predation and starvation.
• Brown adipose tissue plays a role in obesity by increasing energy expenditure and potentially combating obesity.
• Leptin and ghrelin are key hormones in regulating energy balance, with leptin being a satiety hormone and ghrelin being a hunger hormone.
• Pima Indians in northern Mexico, who eat a traditional diet and are physically active, have a much lower incidence of obesity and type 2 diabetes compared to those in Arizona.
• A randomized controlled trial showed that ultra-processed foods led to increased body fat mass and weight, while unprocessed foods had the opposite effect.
• Weight loss surgeries, such as gastric bypass surgery, are increasingly utilized to deal with obesity and type 2 diabetes.
• Gastric bypass surgery has benefits, including weight loss and improved glucose tolerance, but also comes with potential problems such as pouch stretching, band erosion, and nutritional deficiencies.
• Nutritional deficiencies in obesity are caused by poor-quality diets, higher nutrient requirements, alterations in micronutrient metabolism, and invasive obesity treatments.
• Micronutrient deficiencies in obesity include iron, zinc, calcium, magnesium, potassium, selenium, and vitamins A, C, D, and E.