April 2021 Issue

CPE Monthly: Aphrodisiac Foods
By Ginger Hultin, MS, RDN
Today’s Dietitian
Vol. 23, No. 4, P. 46

Suggested CDR Performance Indicators: 8.1.1, 8.1.4, 8.3.1
CPE Level 2

Take this course and earn 2 CEUs on our Continuing Education Learning Library

Since ancient times, humans have sought foods to enhance libido, sexual function, and satisfaction. These specific foods generally are referred to as aphrodisiacs. Some researchers define aphrodisiacs as any food or drug that arouses sexual instinct, induces desire, increases pleasure, and improves performance.1 This word originates from Aphrodite, the ancient Greek goddess of love, beauty, pleasure, passion, and reproduction. Ancient civilizations around the world including the Chinese, Indian, Egyptian, Roman, Greek, indigenous Zulu, and Mesoamerican cultures used food and herbs as medicine to address sexual health.2

Sexual health is a major concern for people worldwide. Globally, an estimated 23% to 63% of reproductive-aged females experience sexual dysfunction.2-4 This includes sexual interest and/or arousal disorders, female orgasmic disorder, and genitopelvic pain and/or penetration disorder.2,3 For men, sexual dysfunction is most often studied in relation to erectile dysfunction (ED); an estimated 10% to 52% of men around the world experience this condition to some degree.2,4,5 Dietitians may get questions from their clients about whether nutrition can impact sexual health and whether aphrodisiac foods could be effective.

Modern evidence on aphrodisiac foods is limited and mixed, and many studies have been done only on animals or in vitro. Large human studies are lacking, primarily because of the complexity of studying human sexuality—including complicated etiology, differences between male and female dysfunction, and many potential treatment targets—as well as a lack of validated research methods, especially for female sexual dysfunction.6

Another challenge is study design. For example, there are many study designs for measuring aphrodisiac properties, ranging from physical methods (eg, mating behavior test, mounting frequency, ejaculation frequency, computed male sexual behavior parameters, and test for libido) to biochemical methods such as determination of testicular and serum cholesterol, hormonal determination, assay for neuronal nitric oxide (NO) synthase, and androgen receptor protein.2 Because studies generally are limited to these metrics, it’s challenging to find large studies, studies on humans, and also consistency in studies regarding how foods and natural substances affect sexual desire and behavior.

Despite the challenges in assessing aphrodisiac properties of food, interest in natural remedies and aphrodisiac foods remains high globally. In modern-day Africa, about 90% of the population relies on traditional and folk medicine practitioners for primary care and herbal medicines for treatment of various illnesses. In India, approximately 70% of the population seeks advice or treatment from traditional practitioners or herbal healers. In China, an estimated 40% of hospitals use some form of traditional medicine. In the United States, 38% of adults reported using traditional medicine including herbal therapy, vitamins, and minerals in 2007.7

This continuing education course reviews the potential for food to be used as an aphrodisiac, including history and traditional uses and modern-day research about food’s ability to boost libido and enhance sexual health.

Physiological Aspects of Sexual Health Conditions
There are many physiological components of sexual health that affect biological males and females, though the factors vary widely. Part of the reason this research is so challenging to interpret is because factors that affect male and female sexual health involve complex systems. Reasons for these disorders stem from many systems in the body. For example, sexual desire is governed by the central nervous system. Other sexual functions are controlled by a variety of hormones including androgens, which are critical to sexual function.2

Sexual function can decline naturally with age or due to chronic diseases including poor blood sugar and blood pressure control. Age is a factor for decreased sexual function in both men and women.8 Biological factors affecting physiology of sexual function can include blood flow and circulation, blood pressure control, blood sugar control, and micronutrient deficiency.9 It’s important to understand that psychological factors also play a strong role and that many sexual health conditions require medical treatment, medications, and/or behavioral therapy or trauma work.

Sexual Health Affecting People Who Are Biologically Female
For women, sexual dysfunction includes sexual interest and/or arousal disorder, female orgasmic disorder, and genitopelvic pain and/or penetration disorder.2,3 Many factors, both mental and physical, are associated with sexual dysfunction in women, including anxiety, depression, stress, fear of sex, visceral adiposity, cigarette smoking, abortion, genitourinary problems, female genital mutilation, relationship dissatisfaction, and sexual abuse.4,9

Age is a factor for decreased sexual function in women. They often experience a significant reduction in sexual desire specifically during peri- and menopause due to hormonal, physical, and changes in work schedules and family obligations, at that stage of life.8

Menopausal and postmenopausal women are commonly treated with hormone replacement therapy, testosterone therapy, and other medications to increase sexual desire. Examples include tibolone, a synthetic combination of estrogen, progesterone, and androgen hormones, and flibanserin, a nonhormonal serotonin agonist/antagonist that’s used off-label to stimulate sexual arousal.8

Sexual Health Conditions Affecting People Who Are Biologically Male
Many physiological processes, such as blood flow, blood pressure, and blood sugar, affect men’s sexual health and cause sexual dysfunction, including premature ejaculation, inhibited ejaculation, ED, reduced libido/arousal, compulsive sexual behavior, orgasmic disorder, and/or failure of detumescence (subsiding from a sexually aroused state).2,3,9

Many conditions, histories, and lifestyle factors increase risk of ED and other forms of sexual dysfunction, including hypertension, hyperlipidemia, diabetes, anxiety, depression, stress, fear of sex, past sexual abuse, poor micronutrient intake, genitourinary problems, relationship dissatisfaction, smoking, low testosterone, stroke, cerebral trauma, Alzheimer’s and Parkinson’s diseases, alcohol and drug abuse, anemia, trauma to or surgery of the pelvis or spine, coronary artery disease, peripheral vascular disease, Peyronie’s disease, and obesity, especially visceral adiposity. In addition, ED is a possible side effect of many classes of medications, including antihypertensives, antipsychotics, and antidepressants.4,9 A randomized, case-controlled study of 177 men by Dursun and colleagues found significant correlations between ED and higher BMI, triglyceride levels, and waist circumference, and lower HDL cholesterol.9

Common oral drugs for ED that improve the arterial blood flow to penile tissue include apomorphine sublingual, sildenafil, vardenafil, tadalafil, papaverine, alprostadil, and avanafil.2,5 Some herbal-based drugs also are used.2

Aphrodisiac Foods
The vitamin, mineral, and antioxidant contents of foods such as chocolate, apples, and red wine are thought to have aphrodisiac properties that could help with sexual dysfunction. The proposed mechanism behind these foods is that they may help improve peripheral vasodilation via activation of the NO system, resulting in the release of the vasodilator neurotransmitters vasoactive intestinal peptide and NO. These changes could cause an increase in blood flow to external genitalia.10

While some potential aphrodisiac foods fall short on research, there’s animal and human evidence available to support the use of apples, chocolate, oysters, pomegranates, and red wine. Most studies have been conducted on men with ED, though there have been some promising studies on women with respect to apples and red wine.

Apples
Apples are a symbol of fertility in several mythological traditions, and they’re depicted as gifts to goddesses and to signify love, life, springtime, and well-being in European Renaissance paintings.11 Apples contain phytoestrogen compounds that have been shown to potentially enhance female sexual function because the structure is similar to estradiol, which can combine with estrogen receptors in humans, creating hormone balance through both antiestrogen and estrogen-like activity.10

A cross-sectional study on 731 premenopausal women (mean age 31.9 years) using the Female Sexual Function Index (FSFI) found that participants who reported eating an apple per day had significantly higher total and lubrication domain scores (p=0.001 each) than women who didn’t. Researchers concluded there’s a potential relationship between apples and female sexual function but that further research is warranted to determine why this is and in which populations is this the case.10

The FSFI is a validated test used throughout many studies on female sexual dysfunction both in healthy women and those with chronic medical conditions. It assesses several factors in six domains including desire, arousal, lubrication, orgasm, satisfaction, and pain.10

Although research on phytoestrogens, such as those found in apples, is limited and inconsistent in humans, researchers hypothesize that because these isoflavonoids are weak estrogen agonists/antagonists, they may be a key in helping researchers better understand endocrine disruptors. Studies have suggested that phytoestrogens may be able to alter estrogen-dependent gene expression in the brain.12 Note that studies on fruit and human sexual enhancement are limited, and there are no strong human studies assessing how apples or other fruit could affect larger groups and/or men.

Chocolate
Historically, chocolate has been thought to increase sexual desire and improve sexual pleasure. There were rumors that the Aztec ruler Montezuma prepared a concoction of cocoa before having sexual intercourse with his wives.13,14 The belief that chocolate had “exhilarating” effects caused Christian groups in 17th-century Europe to create a movement to ban these foods until doctors and scientists fought for them to remain in the diet due to their positive effects when used as medicine.14

But this belief isn’t just part of human history; it also shows up in modern day spending, which is confirmed by how much American consumers invest in chocolate on Valentine’s Day. Modern consumers who purchase chocolate on this romantic holiday often don’t connect it to its long history as a food that may increase sexual desire. An industry report found that consumers spent $1.8 billion on candy for the Valentine’s Day holiday in 2019.15

Research on the aphrodisiac effects of chocolate are limited and mixed, though some studies suggest benefit. Salonia and colleagues studied 163 women and found that those who reported daily chocolate intake scored significantly higher in the desire domain of the FSFI than those who didn’t consume it daily. However, the group who reported daily chocolate intake was significantly younger than the group who didn’t, possibly skewing results.13

Natural Medicines Database cites positive effects of cocoa for CVD, including a 10% lower risk of CVD and 50% lower risk of cardiovascular-related mortality in those who consumed larger vs smaller amounts (based on 2.11 g/day median intake).16,17 A study on 470 elderly men found that systolic and diastolic blood pressure was significantly lower in those with the highest third of cocoa intake.17 As previously discussed, sexual dysfunction, including ED, is affected by CVD, so improvements in cardiovascular health also may support sexual health.

Some researchers posit that chocolate’s potential aphrodisiac properties may be due to the sensual pleasure of consuming chocolate that then enhances the sexual experience. As cocoa generally is combined with sugar and fat, eating chocolate may stimulate the hypothalamus, increasing levels of serotonin in the brain. However, factors such as improvements in cardiovascular health (as discussed in the previous paragraph), as well as antioxidants in cocoa, including catechins, anthocyanins, gallocatechin, and epigallocatchin, may be associated with certain dietary patterns that support human sexual health.18 For example, the Mediterranean diet has been shown to improve sexual function in women with metabolic syndrome (explored more in depth later). This could be partially due to the fact that the intervention group consumed more phytonutrient-rich fruits, vegetables, nuts, whole grains, and olive oil compared with controls, which caused a decrease in inflammatory marker C-reactive protein and improvements in FSFI scores.19

Oysters and Other Marine Animals
Since ancient times, many cultures have connected the oyster to enhanced sexual performance, especially in men. However, human studies to prove this connection are lacking. In a study in which oyster extracts were administered to male mice, researchers found increased mounting behavior (indicating heightened sexual desire) as doses were raised from 50 mg/kg (which showed only mild increase in effect) to 100 and 200 mg/kg. Mounting behavior can be enhanced by elevated testosterone levels and changes in neurotransmitter levels.20

Zinc has been associated with improved sexual health in men due to its role in both sperm production and hormone metabolism, which could be why oysters have been associated with sexual health in the past.20 There’s research, some of it old, that shows zinc may play an important role in testosterone levels in men because deficiency in both humans and mice can cause a significant decrease in serum testosterone in as little as 20 weeks.21 Oysters are extremely high in zinc, with 74 mg (673%) per 3-oz serving.22

A similar mouse study on mounting behavior was conducted using sea slug extract, Aplysia dactylomela, with comparable results, suggesting that this sea creature could be similarly beneficial as oysters due to apparent high levels of steroids in these slugs.23

Some studies indicate that other marine animals, including arthropods such as lobsters and crabs, have been used in traditional medicines and cultures as aphrodisiacs. A literature review states that boiled lobsters were used as aphrodisiacs in the Middle Ages in Europe. Similar to chocolate, lobster meat is soft and exceptionally flavorful, possibly creating a sensory experience in consuming it that some people link to aphrodisiac properties. Though a variety of arthropods are used as aphrodisiacs especially in Asia and South America, there’s no strong current literature to support their use.24

Though oysters and other seafoods are commonly marketed as aphrodisiacs, human research is limited and only some small animal studies done on extracts of these foods have shown any promise.

Pomegranates
Studies done in rats and humans have shown that pomegranate juice may have a benefit to males with ED.25-27 A four-week randomized, placebo-controlled, double-blinded, crossover pilot study of 53 male participants with ED by Forest and colleagues found that 8 oz of pomegranate juice consumed daily with the evening meal improved erections compared with placebo. Though the results weren’t statistically significant, they still suggest that a food such as pomegranate juice with concentrated antioxidants and the potential to increase endothelial NO levels, thereby promoting blood vessel dilation, could hold promise for enhancing sexual health in males with ED.26 Studies by Forest and colleagues and Viuda-Martos and colleagues state that the rich content of phenolics such as lignins, melanins, tannins, and flavonoids (including many anthocyanins) may contribute to the functional benefit of consuming pomegranates for health.26,27

Researchers hypothesize that dietary antioxidants, particularly pomegranate extract, can reduce oxidative stress, increasing penile blood flow as well as erectile activity in some studies. Zhang and colleagues studied the antioxidant potency of pomegranate juice, red wine, blueberry juice, cranberry juice, orange juice, and green tea, concluding that pomegranate juice had the highest antioxidant activity of all the options. Researchers administered to rabbits with atherosclerosis-induced arteriogenic ED either placebo (water) or extracts of 30 mg, 60 mg, or 120 mg polyphenol concentrations from pomegranates per day for eight weeks. They found that arterial pressure was significantly lower in the 120 mg group when compared with placebo (p=0.001) and that all rabbits taking the extract significantly improved erectile function in the ED group when compared with placebo. The extract was thought to lower oxidative damage in the cardiovascular system and improve the intracavernosal blood flow of atherosclerotic animals compared with animals with atherosclerosis receiving placebo, which could then improve blood flow to the penis.28

Red Wine and Alcohol
Light to moderate amounts of red wine may be linked to enhanced sexual function in men and women. A study by Mondaini and colleagues on 789 women aged 18 to 50 without sexual disorders found that daily moderate wine intake (one to two glasses) compared with women who didn’t drink at all and women who drank more than two glasses of red wine, white wine, or other alcoholic beverages had a significantly higher score on the FSFI (p=0.001) in the sexual desire, lubrication, and overall sexual function domains.29

A recent study in Sexual Medicine investigated the association between alcohol use and female sexual dysfunction in 2,253 women using the Alcohol Use Disorders Identification Test and FSFI. Of the 1,649 sexually active women in the study, 57% experienced FSD, 80% reported some level of alcohol use, and 38% reported potentially hazardous drinking patterns. The latter group of women scored higher on the FSFI, which indicated statistically significantly better sexual functioning (p<0.001). Researchers hypothesize that alcohol could benefit women’s sexual functioning by increasing arousal and endogenous estrogen.30 While alcohol intake may be linked with better sexual function, desire, and lubrication, it’s also associated with increased sexual risk-taking.29-32

A meta-analysis of population-based studies found that regular intake of alcohol was negatively associated with ED (p<0.001); however, researchers noted a J-shaped curve regarding alcohol and health similar to what other studies have found, suggesting that a small to moderate amount may be protective but higher levels can be detrimental. The researchers hypothesize that alcohol likely affects cardiovascular outcomes, which in turn impact ED. They concluded that larger studies are needed to better determine the relationship between alcohol and ED.33

Though there’s research on red wine, other alcohol, and increased sexual attraction, as well as physical attributes that benefit sexual function in men and women, dietitians should still educate their clients on the guidelines for alcohol intake, which are a maximum of one drink per day for women and two for men.34,35

Future Research on Aphrodisiac Foods
Unfortunately, many foods often referred to in ancient or modern cultures as aphrodisiacs, including chili peppers, pine nuts, walnuts, figs, asparagus, and garlic, don’t have much research to support their use in humans. However, the Natural Medicines Database cites some potential uses of garlic, including possible effectiveness for atherosclerosis, diabetes, hyperlipidemia, and hypertension, all of which could be useful in reducing sexual dysfunction risk, especially in men.36 Ginger and onion have been used in juice and powder form and tested on rats in small studies, and so they fall in both the whole food and herbal/supplement groups of potential aphrodisiacs. Significant increases in testosterone were seen in rats receiving ginger and onion treatments, but the study was small and the doses were concentrated, not reflecting intake of the whole foods.37

Though research doesn’t support aphrodisiac properties in these foods, compounds in all of these foods, including vitamins, minerals, and antioxidants, potentially could provide benefits for cardiovascular health or blood sugar balance when combined with an overall healthful dietary plan and lifestyle. When these factors have improved, it’s possible that sexual health also could improve.

Aphrodisiac Herbs
While the main focus of this article is food, a variety of herbs are used as aphrodisiacs as well, including chamomile, fenugreek, ginkgo, ginseng, maca, saffron, and Gokshura (Tribulus terrestris), also known as goat’s head. Gokshura supplementation has been shown in animal models to significantly increase testosterone, though these effects haven’t been proven in humans. However, this herb may increase NO levels in humans, leading to positive changes in blood flow.38 Literature reviews on aphrodisiac properties of herbal remedies haven’t demonstrated strong enough evidence to warrant recommendations on the use of any natural remedy for sexual enhancement.39

Dietitians may encounter herbal use in Ayurvedic or natural medicine practice. When counseling on herbal supplements, be sure to educate clients to consult with their practitioners for safety, especially regarding potential interactions with medical conditions, prescription medications, and other over-the-counter medicines or supplements. Many herbals can lower blood sugar or blood pressure, and these effects can be compounded if combined with other medications or supplements. Discuss quality assurance with clients, helping them look for third-party certification seals so they can ensure they’re getting a supplement with correct dosing and that’s uncontaminated.

Dietary Patterns and Sexual Health
Apart from food, dietitians can educate clients about dietary patterns thought to support sexual health and those that generally align with other recommendations for cardiovascular health and blood sugar management.

Maiorino and colleagues studied 215 men and women newly diagnosed with type 2 diabetes over a period of 8.1 years, splitting participants between a low-fat and a Mediterranean diet. Both diets restricted calories to 1,500 kcal for women and 1,800 kcal for men. The participants didn’t experience sexual dysfunction at the beginning of the study but were assessed as at high risk of developing it over time because of their diabetes and other factors such as obesity, hypertension, metabolic syndrome, atherogenic dyslipidemia, or subclinical inflammation. Using validated tests for women (FSFI) and men (International Index of Erectile Function), the researchers found that progression of sexual dysfunction in both sexes was significantly lower in the Mediterranean diet group than the low-fat group (p=0.019 for women and p=0.024 for men). Limitations of this study included an unblinded design and the inability to generalize these results to larger populations with diabetes.40

A literature review by Towe and colleagues found that metabolic syndrome negatively affects sexual function in women, notably in younger, premenopausal women and especially in those with higher BMIs. Similar to the etiology of male ED, blood flow and endothelial health is important for providing adequate blood flow to genitourinary organs. Studies also show that people with eating disorders suffer from sexual dysfunction at higher rates than those without.41

The Mediterranean diet pattern has been studied on male and female sexual health markers, with positive effects in both sexes.19,40-42 In a two-year study on 65 men with ED, participants following a Mediterranean diet consumed more fruits, vegetables, nuts, whole grains, and olive oil and saw greater improvements in endothelial function scores, C-reactive protein, and reduced prevalence of ED (26.7% vs 13%; p=0.03) vs those on the control diet.42

Another review by La and colleagues of studies in men found that some evidence demonstrates that Mediterranean diet patterns lessen ED.43 Improvements in ED also were seen when men with overweight and obesity lost weight through a low-fat, calorie-restricted diet. Standard Western diets were associated with lower semen quality.42

Esposito and colleagues studied 59 women with female sexual dysfunction and metabolic syndrome, assigning 31 of them to a Mediterranean diet for two years. The FSFI improved significantly (p=0.01), and C-reactive protein reduced significantly (p<0.02).19

Diet appears to play a role in both male and female sexual health, with particularly positive outcomes for those with metabolic syndrome. A Mediterranean diet is likely one of the most indicated dietary patterns for sexual health based on initial study results.19,40-43 Many potentially aphrodisiac foods, such as red wine and pomegranates, could fit into a Mediterranean dietary pattern.

Putting It Into Practice
Clients may inquire with dietitians about natural remedies, lifestyle changes, and foods that can improve sexual function and health or alleviate common problems such as ED or low libido. It’s important to work with a patient’s medical team to assess the root of their sexual dysfunction because it may be linked to other health problems such as CVD. Dietitians can work with the medical team to present treatments, including supplements, and lifestyle changes (such as increased exercise, mental health support, or smoking cessation), and recommend certain foods that may increase sexual function as part of an overall healthful eating pattern.

RDs should suggest specific foods in a way that explains the research, which mainly comprises animal studies, smaller human studies, and extracts of foods rather than whole foods. Dietitians should refer to other clinicians to ensure that other conditions, such as cardiovascular and metabolic diseases, are being addressed.

However, eating more oysters, consuming more fruit in the form of apples or pomegranates, and even enjoying dark chocolate or cocoa could have potential benefits to many systems of the body. Dietitians can educate clients that mindful eating may enhance the sensory experience of food, which may account for sexual enhancement effects of some foods due to their impact on pleasure centers in the brain. They should be clear, however, that science in this area is scarce and individual foods shouldn’t be seen as a “cure” for sexual dysfunction. Rather, RDs can help clients incorporate some of the foods mentioned in this article into overall potentially beneficial dietary patterns, such as the Mediterranean diet, as part of the overall picture of sexual health for men and women.

— Ginger Hultin, MS, RDN, is an integrative nutrition specialist and owner of the private practice Champagne Nutrition, PLLC, in Seattle.

Learning Objectives
After completing this continuing education course, nutrition professionals should be better able to:
1. Distinguish the foods with emerging evidence-based aphrodisiac properties.
2. Evaluate why studying aphrodisiac foods for their effects on sexual function is challenging.
3. Develop communication skills to counsel clients who have questions about supporting sexual health through nutrition.

CPE Monthly Examination

1. Which of the following is true about human sexual health conditions and how they may affect males and females around the world?
a. They’re a major concern for both males and females worldwide.
b. They affect males at much higher rates than females.
c. They affect females at much higher rates than males.
d. Evidence of sexual health and dysfunction is lacking and more studies are needed to determine whether they affect males and females more or less.

2. What is the most likely reason cocoa may enhance sexual function?
a. Its high calcium content
b. The sensory pleasure of consuming it
c. Its blood sugar–lowering effects
d. The younger age of people who tend to consume it

3. Why have oysters traditionally been considered an aphrodisiac food?
a. They have similar effects as other aphrodisiacs, including arthropods.
b. They’ve been demonstrated to have effect in some small but significant human studies.
c. They have a unique antioxidant status, which plays a role in sperm production.
d. They have a high zinc content, which plays a role in sperm production.

4. In studies by Viuda-Martos and colleagues and Forest and colleagues, which antioxidants were thought to contribute to the health benefits of pomegranates?
a. Antioxidant vitamins C and E
b. Phenolic compounds including quercetin and catechins
c. Phenolic compounds including anthocyanin flavonoids
d. Flavonoids including coumaric acid and selenium

5. How should dietitians counsel clients on the relationship between alcohol and sexual function?
a. Continue to recommend clients limit alcohol consumption to one drink per day for women and two drinks per day for men.
b. Educate clients that increased intake of alcohol is positively associated with sexual function and that it could benefit sexual health.
c. Continue to recommend that clients limit alcohol to fewer than three drinks per week.
d. Counsel clients that alcohol consumption reduces inflammation.

6. Studies done on men and women with metabolic syndrome and sexual dysfunction found which of the following?
a. Improved sperm count and higher testosterone levels on a Mediterranean diet
b. Improvements in sexual function markers and cholesterol on a vegetarian diet
c. Improvements in metabolic syndrome markers including blood pressure and cholesterol on a low-carb diet
d. Improvements in sexual function markers and decreased C-reactive protein on a Mediterranean diet

7. What has been found regarding the relationship between apple consumption and sexual health?
a. Apple consumption may benefit male sexual health.
b. Apple consumption may benefit female sexual health.
c. Results weren’t significant enough to determine a benefit.
d. The fiber and vitamin C in apples is likely responsible for any benefits.

8. What amount of pomegranate juice or pomegranates is thought to improve symptoms of erectile dysfunction in men?
a. Pomegranate juice intake hasn’t been found to be effective for erectile dysfunction.
b. 16 oz pomegranate juice per day
c. 8 oz pomegranate juice per day
d. One whole pomegranate per day

9. Which of the following lifestyle factors may negatively affect
sexual health?
a. Taking vitamins over the Tolerable Upper Intake Limits
b. Having an eating disorder
c. Sleeping more than eight hours per night
d. Exercising excessively

10. The key herbs used in ancient and traditional medicine as aphrodisiacs include which of the following?
a. Oregano, sage, epazote, mint, comfrey, and borage
b. Thyme, winter savory, lemongrass, sorrel, and tarragon
c. Coriander, stevia, chive, lavender, and Vitex Agnus-Castus
d. Chamomile, fenugreek, ginkgo, ginseng, maca, and Tribulus terrestris

References
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2. Patel DK, Kumar R, Prasad SK, Hemalatha S. Pharmacologically screened aphrodisiac plant — a review of current scientific literature. Asian Pac J Trop Biomed. 2011;1(1):S131-S138.

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5. Nimesh S, Tomar R, Kumar M, Tyagi N, Shukla PK. Erectile dysfunction: an update. Advances Med Dental Health Sci. 2019;2(1).

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8. Pellow J, McGrath L. Herbal medicine for low sexual desire in menopausal women: a clinical review. Complement Ther Clin Pract. 2016;25:122-129.

9. Dursun M, Besiroglu H, Cakir SS, Otunctemur A, Ozbek E. Increased visceral adiposity index associated with sexual dysfunction in men. Aging Male. 2018;21(3):187-192.

10. Cai T, Gacci M, Mattivi F, et al. Apple consumption is related to better sexual quality of life in young women. Arch Gyn Ob. 2014;290(1):93-98.

11. Apple symbolism in art. Arthive website. https://arthive.com/encyclopedia/68~Apple_symbolism_in_art. Accessed April 6, 2020.

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13. Salonia A, Fabbri F, Zanni G, et al. Chocolate and women’s sexual health: an intriguing correlation. J Sex Med. 2006;3(3):476-482.

14. Lippi D. Chocolate in history: food, medicine, medi-food. Nutrients. 2013;5(5):1573-1584.

15. Valentine’s Day spending to reach record of $20.7B. Candy Industry website. https://www.candyindustry.com/articles/88538-valentines-day-spending-to-reach-record-207b. Published February 12, 2019. Accessed February 24, 2020.

16. Cocoa. Natural Medicines Database website. https://naturalmedicines.therapeuticresearch.com/databases/food,-herbs-supplements/professional.aspx?productid=812. Updated July 25, 2019. Accessed February 24, 2020.

17. Buijsse B, Feskens EJM, Kok FJ, Kromhout D. Cocoa intake, blood pressure, and cardiovascular mortality: the Zutphen Elderly Study. Arch Intern Med. 2006;166(4):411-417.

18. Afoakwa EO. Cocoa and chocolate consumption — are there aphrodisiac and other benefits for human health? S Afr J Clin Nutr. 2008;21(3):107-113.

19. Esposito K, Ciotola M, Giugliano F, et al. Mediterranean diet improves sexual function in women with the metabolic syndrome. Int J Impotent Res. 2007;19(5):486-491.

20. Ridzwan BH, Hanani M, Norshuhadaa MS, Hanis ZF, Aileen TS. Screening for aphrodisiac property in local oyster of Crassostrea iredalei. World Appl Sci J. 2013;26(12):1546-1551.

21. Prasad AS, Mantzoros CS, Beck FW, Hess JW, Brewer GJ. Zinc status and serum testosterone levels of healthy adults. Nutrition. 1996;12(5):344-348.

22. Zinc fact sheet for health professionals. National Institutes of Health Office of Dietary Supplements website. https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/. Updated July 15, 2020. Accessed April 6, 2020.

23. Hashim R, Roslan NA, Zulkipli FH, Daud JM. Screening of aphrodisiac property in sea slug, Aplysia dactylomela. Asian Pac J Trop Med. 2014;7S1:S150-S154.

24. Pajovic B, Radosavljevic M, Radunovic M, Radojevic N, Bjelogrlic B. Arthropods and their products as aphrodisiacs — review of literature. Eur Rev Med Pharmacol Sci. 2012;16(4):539-547.

25. Onal E, Yilmaz D, Kaya E, Bastaskın T, Bayatlı N, Gur S. Pomegranate juice causes a partial improvement through lowering oxidative stress for erectile dysfunction in streptozotocin-diabetic rat. Int J Impot Res. 2016;28(6):234-240.

26. Forest CP, Padma-Nathan H, Liker HR. Efficacy and safety of pomegranate juice on improvement of erectile dysfunction in male patients with mild to moderate erectile dysfunction: a randomized, placebo-controlled, double-blind, crossover study. Int J Impot Res. 2007;19(6):564-567.

27. Viuda‐Martos M, Fernández‐López J, Pérez‐Álvarez JA. Pomegranate and its many functional components as related to human health: a review. Comp Rev Food Sci Food Saf. 2010;9(6):635-654.

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