Superfoods Research & Evidence-Based Practice 5

Question 1

In a crossover trial comparing chia seeds to flaxseeds for omega-3 status, a 'washout period' between phases is included to:

Accepted Answer

Eliminate carryover effects from the first treatment before beginning the second

Answer

A washout period allows any physiological or biochemical changes from the first intervention to return to baseline before participants begin the second, ensuring clean comparisons.

Question 2

The concept of 'nutrigenomics' is most relevant to superfood research because it examines how:

Accepted Answer

Individual genetic variation affects responses to dietary bioactive compounds

Answer

Nutrigenomics studies interactions between genes and nutrients, explaining why individuals with different SNPs (e.g., in MTHFR or COMT) may respond differently to the same superfood.

Question 3

A study shows that participants who ate kale daily for 8 weeks had significantly lower LDL cholesterol. The study had no control group. The most significant methodological concern is:

Accepted Answer

Regression to the mean — participants may have had unusually high LDL at baseline that would improve regardless

Answer

Without a control group, it is impossible to distinguish the effect of kale from natural fluctuation back toward average values (regression to the mean) or other concurrent lifestyle changes.

Question 4

Which scientific body publishes the Dietary Reference Intakes (DRIs) that researchers use to contextualize superfood nutrient findings in the US?

Accepted Answer

National Academies of Sciences, Engineering, and Medicine

Answer

The National Academies of Sciences, Engineering, and Medicine establishes DRIs (including RDAs, AIs, and ULs) through expert panels reviewing the available evidence base.

Question 5

A researcher wants to study the long-term effect of pomegranate juice on cardiovascular disease incidence over 20 years. The most feasible design is:

Accepted Answer

Prospective cohort study with dietary assessment at baseline and follow-up

Answer

A 20-year RCT with a food is impractical; a prospective cohort can follow large groups naturally over decades, measuring dietary habits and tracking cardiovascular outcomes.

Superfoods Practice Test

Superfoods Practice Test

Superfoods Research & Evidence-Based Practice 5