The goal of this study is to determine whether erectile function is impacted by dietary patterns in healthy men with normal erectile function.

Visit 1:

After reviewing and signing consent, subjects will be screened for the study. Screening will consist of the following:

• Complete International Index of Erectile Function (IIEF) questionnaire.
• Record medical history, concomitant medications
• Measure height and weight, calculate BMI
• Vitals
• Draw blood for total testosterone, sex hormone binding globulin and Thyroid Stimulating Hormone
• Query subject regarding the presence of genital rash or lesions. Subjects will be asked, "do you have a rash or lesion on your penis or surrounding area?"

If the IIEF score is abnormal, subjects will be advised to contact their primary care provider.

Each subject will be contacted by phone with their blood results. If abnormal subject will be given the recommendation to contact his primary care provider.

If an abnormal finding is identified during screening, such as an abnormal STOP-bang score, subject will be given the recommendation to contact his primary care provider.

If the subject has no primary care provider, contact information for primary care will be given.

Subjects meeting inclusion and exclusion criteria will be randomized into the study, into either Sequence One or Sequence Two. Once enrolled, subjects will be asked to not modify their dietary habits throughout the duration of the study other than during the two evenings and two full days when food is provided (see below).

Sequence One:

Visit 2:

Subjects will return to the study center in the morning after having fasted (other than consuming water) since 11pm the night before. They will have been asked to not brush their teeth or use mouthwash and/or other breath fresheners that morning. Anthropomorphic and blood pressure and heart rate recordings will be made. Saliva will be stored for NO measurement. Blood will be drawn and stored. Urine will be collected and stored.

Subjects will be taught how to use the Rigiscan™ device. Subjects will receive one plant-based dinner (food will be provided by Montefiore-Einstein Food Services.) Subjects will then leave the study center and they will consume their usual diet until 5pm. For the rest of the evening until 11pm they will consume only the dinner provided. Water will be the only beverage allowed after 5pm. Dinner should be consumed at 8:30pm EST. Subjects will text pictures of everything they consume (eat or drink) after 5pm to Dr. Ostfeld or to a study representative and s/he will have text or verbal contact with the subject at least once that evening. That night, subjects will do a Rigiscan™ assessment overnight at their home. The time the subject goes to bed and the time the subject wakes up for the day should be recorded. The subject agrees to be in bed with Rigiscan™ on (other than for emergency or needed trips to the bathroom) for at least seven hours.

Visit 3 Subjects will return to the study center the morning after the Rigiscan™ assessment and bring the Rigiscan™ device with them. They will have been fasting other than drinking water since 11pm the night before. They will have been asked to not brush their teeth or use mouthwash and/or other breath fresheners that morning. Anthropomorphic and blood pressure and heart rate recordings will be taken. Saliva will be stored for NO measurement. Blood will be drawn and stored. Urine will be collected and stored.

Subjects will then receive one full day of plant-based meals (food will be provided by Montefiore-Einstein Food Services.) Subjects will be encouraged to eat breakfast at the study center after the initial anthropomorphic measures are made, saliva is obtained, and blood is drawn. Subjects will text pictures of all they consume during that day to Dr. Ostfeld and/or to a study representative and s/he will have text or verbal contact with the subject at least twice during that day. Dinner should be consumed at 8:30pm, EST. Subjects will fast other than water after 11pm. That night, subjects will do a Rigiscan™ assessment overnight at their home. Black coffee and/or tea is permitted only before noon. The time the subject goes to bed and the time the subject wakes up for the day should be recorded. The subject agrees to be in bed with Rigiscan™ on (other than for emergency or needed trips to the bathroom) for at least seven hours.

Visit 4 Subjects will return to the study center the morning after the Rigiscan™ assessment and bring the Rigiscan™ device with them. They will have been asked to not brush their teeth or use mouthwash and/or other breath fresheners that morning. Anthropomorphic and blood pressure and heart rate recordings will be taken. Saliva will be stored for NO measurement. Blood will be drawn and stored. Urine will be collected and stored.

There will then be a washout period for 8-12 days and subjects will be instructed to return to their usual dietary habits during this washout period. Number of days of the washout period will be recorded.

Visit 5 After the washout period, subjects will return to the study center in the morning after having fasted (other than consuming water) since 11pm the night before. They will have been asked to not brush their teeth or use mouthwash and/or other breath fresheners that morning. Anthropomorphic and blood pressure and heart rate recordings will be taken. Saliva will be stored for NO measurement. Blood will be drawn and stored. Urine will be collected and stored.

Subjects will receive one animal-based dinner (food will be provided by Montefiore-Einstein Food Services.) Subjects will then leave the study center and they will consume their usual diet until 5pm. For the rest of the evening until 11pm they will consume only the dinner provided. Water will be the only beverage consumed after 5pm. Dinner should be consumed at 8:30pm, EST. Subjects will text pictures of all they consume (eat or drink) after 5pm to Dr. Ostfeld or to a study representative and s/he will have text or verbal contact with the subject at least once that evening. Subjects will fast other than water after 11pm. That night, subjects will do a Rigiscan™ assessment overnight at their home. The time the subject goes to bed and the time the subject wakes up for the day should be recorded. The subject agrees to be in bed with Rigiscan™ on (other than for emergency or needed trips to the bathroom) for at least seven hours.

Visit 6 Subjects will return to the study center the morning after the Rigiscan™ assessment and bring the Rigiscan™ device with them. They will have been asked to not brush their teeth or use mouthwash and/or other breath fresheners that morning. Anthropomorphic and blood pressure and heart rate recordings will be taken. Saliva will be stored for NO measurement. Blood will be drawn and stored. Urine will be collected and stored.

Subjects will then receive one full day of animal-based meals (food will be provided by Montefiore-Einstein Food Services.) Subjects will be encouraged to eat breakfast at the study center after the initial anthropomorphic measures are made, saliva is obtained, and blood is drawn. Subjects will text pictures of all they consume during that day to Dr. Ostfeld and/or to a study representative and s/he will have text or verbal contact with the subject at least twice during that day. Dinner should be consumed at 8:30pm, EST. Subjects will fast other than water after 11pm. That night, subjects will do a Rigiscan™ assessment overnight at their home. Black coffee and/or tea is permitted only before noon. The time the subject goes to bed and the time the subject wakes up for the day should be recorded. The subject agrees to be in bed with Rigiscan™ on (other than for emergency or needed trips to the bathroom) for at least seven hours.

Visit 7 (End of Study) Subjects will return to the study center the morning after the Rigiscan™ assessment and bring the Rigiscan™ device with them. They will have been asked to not brush their teeth or use mouthwash and/or other breath fresheners that morning. Anthropomorphic and blood pressure and heart rate recordings will be taken. Saliva will be stored for NO measurement. Blood will be drawn and stored. Urine will be collected and stored.

Sequence Two:

Sequence Two is identical to Sequence One, except that the order of the plant-based and animal-based meals is reversed.

Inclusion Criteria:

• Subject provides written informed consent and HIPAA authorization in English before any study procedures are conducted.
• Subject is taking no medical therapy other than: prn MDIs, medication(s) for anxiety, depression, and/or ADHD (these medications include, but are not limited to, SSRIs, SNRIs, Stimulants), no change in supplements if applicable.

The anxiety, depression, and/or ADHD will have been controlled (per report of subject) for the last 6 months.

• IIEF score greater or equal to 22
• Subject will have had penile-sexual intercourse (either vaginal or anal penetration) within 12 weeks of enrollment.
• Male aged 18-35 years old
• Lives within commuting distance of Montefiore Health System
• Subject's significant other (if applicable) agrees to support the subject during the study
• Subject agrees to photograph and share all items consumed/drunk during the dietary intervention
• Subject agrees to avoid all illicit drugs, NSAIDS, and alcohol for at least two days prior to Rigiscan™ recording and on the days and nights of Rigiscan™ recording
• Subject agrees to refrain from sexual activity for at least 24 hours prior to Rigiscan™ placement and to have no sexual activity on the days and nights of Rigiscan™ recording.
• Subject agrees to not view, read, or otherwise consume erotic or pornographic material for 24 hours prior to both the days and nights of Rigiscan™ recording and on the days and nights of Rigiscan™ recording.
• Subject agrees to not have an orgasm for 24 hours prior to both the days and nights of RigiscanTM recording and on the days and nights of Rigiscan™ recording.
• Subject agrees to come to Montefiore to undergo Rigiscan™ training
• Subject agrees to only consume/drink permitted food/beverages.
• Subject agrees to attend all in person visits at Montefiore, to begin fasting at 11pm the night before each visit, and to undergo all blood draws/salivary/other testing.
• Subject agrees to not use mouthwash or mouth rinses or intentionally spit for the entire duration of the study. Subjects will be asked to refrain from using mouthwash for at least 2 days prior to enrollment. Subject agrees to not brush his teeth in the morning of the day of each study visit. Tooth brushing is otherwise permissible.
• BMI <30, BMI >=18.5, weight >110 lbs.
• Subject agrees to comply with the study procedures and visits.
• Subject exercises for at least 15 minutes at least two times per week
• If exercise is done, subjects will exercise for the same amount of time and at a similar intensity each day of Rigiscan™ testing. Otherwise, no exercise will be performed on Rigiscan™ days.
• If enrolled, subjects agree to not modify their dietary habits throughout the duration of the study other than during the two evenings and two full days when food is provided.

Exclusion Criteria:

• Relevant dietary allergy
• Vegetarian or Vegan dietary pattern
• History of an eating disorder and/or food addiction
• Hypertension and or history of hypertension with or without medical treatment. Systolic blood pressure > 150mmHg and/or diastolic blood pressure >100mmHg on Visit one. Heart rate >99 on Visit one. Systolic blood pressure < 85mmHg and/or diastolic blood pressure < 50mmHg on Visit one. Heart rate < 35 on Visit one.
• BMI >=30, BMI <18.5, or weight <= 110lbs
• Known chronic medical disease other than non-inflammatory musculoskeletal disease, asthma, anxiety, depression, and/or ADHD.

Subjects who have had changes in the dosage or type of their medication(s) for anxiety, depression, and/or ADHD within 3 months of enrollment.

Subjects who have scheduled or planned medication and/or medication dose changes during the study period. These medication changes include the initiation of a new medication, discontinuation of a medication, modification of medication dose, and/or the route of administration of a medication.

Subjects who are taking benzodiazepines and/or beta blockers

• History of kidney disease or hyperkalemia
• Subject has received an investigational drug within 30 days prior to signing consent
• Erectile dysfunction
• Has any condition (e.g., psychiatric illness) or situation that, in the investigator's opinion, may confound the study results, or may interfere significantly with the patient's ability to adhere with study procedures
• Currently undergoing treatment for Peyronie's Disease
• Abnormal Testosterone or Thyroid Stimulating Hormone level
• Treated hypogonadism or hypothyroidism
• Planned travel during the study
• The subject is trans-gender
• History of substance abuse in the last 12 months
• Illicit drug use, smoking, or vaping within 4 weeks
• Upper respiratory illness within two weeks on screening
• If profession requires being on call, no overnight or on call duties during the study
• Subject reports any communicable skin or venereal disease
• Subject reports rash or lesion on the penis or surrounding area.
• STOP-Bang score > 2
• Having the diagnosis of Restless Leg Syndrome.
• Having insomnia as defined by: Subject with insomnia would have difficulty initiating or maintaining sleep (30 minutes or more at sleep initiation or 30 minutes or more to fall back asleep if wakes during the night). The above occurs at least 3 times per week for at least 1 month. Furthermore, there must be adequate opportunity for sleep and there must be associated morbidity (feels tired during the day). Definition based on: The International Classification of Sleep Disorders - Third Edition (ICSD-3), 2014.

Outcomes assessor will be blinded to randomization group and order of testing.