The RD exam, formally known as the Registration Examination for Dietitians, is a challenging and comprehensive assessment for men and women who wish to enter this exciting and fast-paced field of health care. This exam is developed by the Commission on Dietetic Registration in consultation with an expert team of exam administrators.
The exam includes a minimum of 125 multiple-choice questions, 25 of which are pretest questions used to develop future versions of the exam. Pretest questions do not contribute to the final score and are impossible to identify. The exam takes approximately three hours to complete.
The content of the RD exam is divided into five content domains:
- The food and nutrition sciences domain (12 percent of the exam) covers food science, the nutrient composition of foods, nutrition, and supporting sciences.
- The section on nutrition care process and model – complex conditions (40 percent) addresses food science, the nutrient composition of foods, nutrition, and supporting sciences.
- Counseling, communication, education, and research (10 percent) includes nutrition screening, assessment, diagnosis, intervention, monitoring, and evaluation.
- The food-service systems domain (17 percent) covers menu planning; procurement, production, distribution, and service; sanitation and safety; and facility planning.
- The section on management (21 percent) addresses human resources, finance and materials, marketing products and services, functions and characteristics, and quality improvement.
Exam scores are available immediately upon completion. The score report includes a scaled score and an indication of the minimum passing scaled score. Candidates will also receive two individual scores for the first three and last two content domains. The scaled score is created by taking the raw score (the number of questions answered correctly) and placing it on a scale of 1 to 50 with a formula that takes into account the relative difficulty of the RD exam version.
RD Exam Practice Questions
1. All of the following are TRUE about essential fatty acidsEXCEPT:
a. Good sources of essential fatty acids include fatty fish such as salmon and tuna.
b. They are available mainly through diet but the human body is able to make a limited supply.
c. Essential fatty acid deficiency can affect growth, wound healing, and vision and cause a scaly skin rash.
d. Alpha-linoleic acid and linoleic acid cannot be synthesized by the human body.
2. Which of the following enzymes assist in the digestion of protein?
a. Lipase and amylase
b. Ptyalin and maltase
c. Sucrase and dextrinase
d. Pepsin and trypsin
3. The primary role of the large intestine is:
a. Water and sodium resorption
b. Water and sodium excretion
c. Fatty acid digestion
d. Performs the majority of the digestive processes
4. If an average adult consumed 20 kcal/kg per day, what do you think the consequence would be?
a. Weight gain
b. Weight loss
c. Weight maintenance
d. Depends upon how much exercise the person gets
5. Beriberi is a deficiency caused by:
1. B: Alpha-linoleic acid and linoleic acid are essential fatty acids (EFAs) that cannot be synthesized in the human body and must be consumed through the diet. Alpha-linoleic acid is a precursor to eicosapentaenoic acid and docosahexaenoic acid. Linoleic acid is the precursor for arachidonic acid. EFAs have a wide range of functions and many are still under investigation. These acids have a role in vision and brain development, may also play a role in reducing cardiovascular risk, and may act as anti-inflammatory agents. EFAs may also play a role in the treatment of certain neurologic and mental disorders such as Alzheimer’s disease and bipolar disorder. The research is ongoing regarding the benefits of EFAs. Fatty fish are a great source of EFAs and so are certain types of vegetable oil such as safflower, sunflower, and flaxseed oil.
2. D: The enzyme pepsin is present in gastric juice and works to hydrolyze peptide bonds into polypeptides and amino acids. Trypsin is found in exocrine secretions from the pancreas and works to hydrolyze peptide bonds as well. Other enzymes that have a role in protein digestion include chymotrypsin, carboxypeptidase, aminopeptidase, and dipeptidase. Protein digestion begins in the stomach primarily by the action of pepsin. Pepsin requires the presence of hydrochloric acid in order to be converted from its inactive form called pepsinogen. The end product of protein digestion is amino acids.
3. A: The large intestine is also known as the colon. The large intestine is made up of the cecum, ascending colon, transverse colon, descending colon, and sigmoid colon. The primary role of the large intestine is water and sodium resorption. As much as 10 liters of water derived from food and secretions enter the large intestine throughout the day. Most of this water is reabsorbed in the colon. Any alteration in this process can lead to massive diarrhea and dehydration. The large intestine also absorbs vitamin K produced by bacteria found in the colon. The majority of the digestion and absorption of food has already occurred once the food reaches the large intestine. The remnants of the digestion process continue to move through the large intestine in the form of waste until it is ultimately excreted.
4. B: The average adult without any major stresses will typically require approximately 30-35 kcal/kg daily. If this same person becomes stressed with an injury, infection, or other insult, daily calorie requirements may increase to above 35 kcal/kg. A range of 20-25 kcal/kg per day is typically used to promote weight loss. These are just quick rules of thumb and there are alternative ways to estimate energy requirements. The Harris Benedict equation calculates basal energy expenditure. Activity and/or stress factors are added to the equation to get an estimation of calorie requirements. Calorie requirements can also be measured by indirect calorimetry, which measures the resting metabolic rate. That rate is about 10-20% higher than the basal metabolic rate.
5. C: Beriberi is caused by a thiamin deficiency. Beriberi is a type of neuropathy with symptoms of mental confusion, difficulty with speech, difficulty ambulating, loss of sensation in hands and feet, tingling sensations, and erratic eye movements. It is a rare disorder because many foods are now fortified with a variety of nutrients, including thiamin. People with chronic alcohol abuse have a greater risk of developing beriberi because of poor nutrition and poor absorption of thiamin related to the alcohol abuse. There is also a genetic form of beriberi. Food sources of thiamin include enriched whole grains, lean meats such as pork, fish, and dried beans. People with chronic alcohol abuse should take a thiamin supplement.