Answers to Self-Assessment Questions - ACCP

2:16-hydroxyestrone ratio in postmenopausal women depends
on equol production status but is not influenced by probiotic
consumption. J Nutr 2005;135:603–8.
78. Answer: C
A patient who has been taking green tea extract for weight
loss is complaining that the product is not working for her.
The weight loss effects of green tea and green tea extract
are believed to be related to their caffeine and catechin
content. Therefore, Answer A (the product contains too
much catechin relative to the caffeine content) is incorrect.
Guarana or mate could be found in combination with green
tea extract in some weight loss products. Although these
combinations might be expected to increase the adverse
effect potential of the product, natural sources of caffeine,
guarana, and mate would be expected to potentiate the
effects of green tea extract on weight loss rather counteract
them (Answer B); thus Answer B is incorrect. Habitually
high consumption of caffeine can accentuate weight loss
during green tea therapy, whereas habitually high caffeine
consumption is a risk factor for weight regain after weight
loss. Thus, Answer C (habitually low caffeine consumption
may attenuate the effect of the green tea extract) is correct.
The antiangiogenic effect of green tea extracts may attenuate
the growth of new adipose tissue (Answer D); however, this
effect would not explain why the patient is not losing weight
while taking the extract, making Answer D incorrect.
1. Cooper R, Morre J, Morre DM. Medicinal benefits of green
tea. Part I. Review of noncancer health benefits. J Altern Comp
Med 2005:11:521–8.
2. Westerterp-Plantenga MS, Lejeune MP, Kovacs EM. Body
weight loss and weight maintenance in relation to habitual
caffeine intake and green tea supplementation. Obes Res
2005;13:1195–204.
79. Answer: A
T.K. is a 52-year-old, overweight, postmenopausal
woman seeking advice regarding incorporating more soy
into her diet. In T.K., who consumes a high animal protein/
high-fat diet, the incorporation of several servings of soyderived
foods daily (taken in place of animal-derived foods)
likely would result in a diet more in line with the saturated fat
and cholesterol content suggested in the Dietary Guidelines
for Americans. Such a diet could thus help reduce her
LDL-C. Although not all studies of soy show benefit in
LDL-C lowering or alleviation of vasomotor symptoms
of menopause, some studies do show benefit. Therefore,
Answer A (incorporating several servings of soy per day
could modestly help her vasomotor symptoms and lower
LDL-C) is the correct answer. Answer B (consumption
of three to five servings of soy-derived foods per week)
would not supply the 30 g of soy protein per day necessary
to contribute to enough weight loss to improve the blood
lipid profile or alleviate vasomotor symptoms. Therefore,
Answer B is incorrect. Answer C, which states erroneously
that several servings per day are unlikely to result in any
health benefit but may increase her risk of endometrial
cancer, is incorrect. Answer D (risks of several servings per
week include a greater chance of developing endometrial
hyperplasia or breast cancer and would outweigh any benefit)
postulates a connection between a modest consumption of
soy and detrimental effects on endometrial and breast tissue
that is highly unlikely; therefore, Answer D is incorrect.
1. Lethaby AE, Brown J, Marjoribanks J, Kronenberg F,
Roberts H, Eden J. Phytoestrogens for vasomotor menopausal
symptoms. Cochrane Database of Systematic Reviews
2007;4:CD001395.
2. St-Onge MP, Claps N, Wolper C, Heymsfield SB.
Supplementation with soy-protein–rich foods does not enhance
weight loss. J Am Diet Assoc 2007;107:500–5.
3. Reynolds K, Chin A, Lees KA, Nguyen A, Bujnowski D, He J.
A meta-analysis of the effect of soy protein supplementation on
serum lipids. Am J Cardiol 2006;98:633–40.
4. Taku K, Umegaki K, Sato Y, Taki Y, Endoh K, Watanabe S.
Soy isoflavones lower serum total and LDL cholesterol in
humans: a meta-analysis of 11 randomized controlled trials.
Am J Clin Nutr 2007;85:1148–56.
80. Answer: C
A meta-analysis included five studies that evaluated the
effect of soy isoflavone on LDL-C concentrations. Data
from the studies are summarized in the following table:
LDL-C
Concentrations
(mmol/L) with High
Isoflavone Intake
LDL-C
Concentrations
(mmol/L) with Low
Isoflavone Intake
Weighted Mean
Difference
(95% confidence
interval)
3.83 3.85 −0.02 (−0.32, 0.28)
3.83 3.80 0.03 (−0.29, 0.35)
2.14 2.31 −0.17 (−0.31, −0.03)
2.86 2.87 −0.01 (−0.29, 0.27)
3.01 3.22 −0.21 (−0.35, −0.07)
Total
−0.14 (−0.23, −0.06)
With these types of data, a 95% confidence interval that
crosses on both sides of 0 means that there is no statistical
difference between treatment groups. Because the
aggregated weighted mean difference for all of the studies
in this meta-analysis was –0.23 to –0.06, it did not cross 0,
indicating a benefit for one of the therapies over the other.
Thus, Answer D (has no statistically significant effect on
LDL-C) is incorrect. Answer A (raises the effect of soy
isoflavone intake on LDL-C in a statistically significant
fashion) is incorrect. Results from four of the five studies
showed lower LDL-C concentrations with high isoflavone
intake compared with low isoflavone intake; therefore, the
aggregated value represents a benefit for high isoflavone
intake (Answer C, lowers LDL-C in a statistically significant
fashion) rather than a detrimental effect (Answer B, raises
LDL-C in a non-statistically significant fashion), making
Answer C correct and Answer B incorrect.
1. Zhuo XG, Melby MK, Watanabe S. Soy isoflavone intake
lowers serum LDL cholesterol: a meta-analysis of 8 randomized
controlled trials in humans. J Nutr 2004;134:2395–400.
2. Guller U, DeLong E. Interpreting statistics in medical literature:
a vade mecum for surgeons. J Am Coll Surg 2003;198:441–58.
Gastroenterology and Nutrition Answers
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Pharmacotherapy Self-Assessment Program, 6th Edition