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Are Soy Foods Safe? | Mark Messina, PhD | The Proof Podcast EP #258
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Are Soy Foods Safe? | Mark Messina, PhD | The Proof Podcast EP #258

The Effect of Soy on Thyroid Hormones

In this section, the speaker discusses the clinical studies conducted on soy and its effect on thyroid hormones. The controversy surrounding soy consumption and its impact on thyroid health is addressed.

Clinical Studies on Soy and Thyroid Hormones

  • A meta-analysis of 18 clinical studies conducted in 2019 found no significant effect of soy or isoflavones (phytoestrogens) on the two main thyroid hormones.
  • These clinical studies have helped resolve the concerns regarding soy's impact on thyroid health.

Introduction to Mark Messina PhD

This section introduces Mark Messina, a renowned expert on the health effects of soy foods and phytoestrogens. The topics to be discussed in the podcast episode are outlined.

Introduction to Mark Messina PhD

  • Mark Messina is an internationally recognized expert on the health effects of soy foods and phytoestrogens.
  • The podcast episode will cover various aspects related to soy consumption, including its history, controversies, safety for infants and young girls, breast cancer risk, male hormone levels, microbiome role, isoflavone content in different soy foods, allergies, and organic vs. non-organic soy.

History of Soy Consumption

This section delves into the history of soy consumption by humans. The archaeological evidence suggests that people have been consuming soybeans for thousands of years.

History of Soy Consumption

  • Archaeological evidence indicates that people may have been consuming soybeans as early as 7,000 years ago.
  • Bill Shurtleff's research suggests that written records show a couple thousand years' history of human consumption of soy foods.

Soy's Controversial Status

This section explores when soy became a controversial figure in dietary discussions and the reasons behind its polarizing status.

Soy's Controversial Status

  • Soy started gaining mainstream popularity in non-Asian countries during the late 1960s and early 1970s, particularly with the rise of vegetarianism and tofu consumption.
  • In the early 1990s, research began to surface suggesting potential health benefits of soy, leading to increased attention on functional foods and phytochemicals.
  • The National Cancer Institute funded significant research on soy's role in reducing cancer risk, which brought attention to its potential health benefits beyond nutrient content.
  • However, controversies arose regarding isoflavones' effects on breast cancer patients' prognosis, growth and development concerns, and thyroid health.

Isoflavones and Health Benefits

This section focuses on the role of isoflavones (plant estrogens) found in soybeans and their impact on health. The unique properties of soy as a source of protein and fat are discussed.

Isoflavones and Health Benefits

  • Soybeans are higher in protein compared to other beans but also contain a significant amount of fat (almost 50% of calories).
  • The high isoflavone content distinguishes soybeans from other foods. A diet rich in soy will have high levels of isoflavones, while a diet without soy will lack them.
  • Isoflavones received attention for their potential health benefits starting from the early 1990s until today.

Controversies Surrounding Isoflavones

This section addresses the controversies surrounding isoflavones found in soy, including concerns about breast cancer patients, growth and development, and thyroid health.

Controversies Surrounding Isoflavones

  • Concerns were raised about isoflavones potentially worsening the prognosis of breast cancer patients and affecting growth and development.
  • Thyroid health was also a topic of concern regarding the impact of isoflavones.

The Soy Institute

This section provides information about the Soy Institute, where Mark Messina serves as the Director of Nutrition Science and Research.

The Soy Institute

  • Mark Messina is associated with the Soy Institute as the Director of Nutrition Science and Research.
  • Further details about the establishment and background of the institute are not provided in this transcript.

New Section

In this section, the speaker discusses the safety of consuming soy and addresses concerns about male feminization.

Soy Consumption and Safety

  • Consuming large amounts of soy, such as Archer, is safe.
  • A meta-analysis of 41 clinical studies found no effects of soy on testosterone or estrogen levels.
  • The speaker is convinced that soy is safe based on human data and observational studies.
  • The dose of soy consumption is important, and overconsumption may have deleterious effects.
  • It is recommended not to consume more than four servings of soy per day.

New Section

This section delves deeper into the dosage and effects of isoflavones in soy consumption.

Importance of Dose in Soy Consumption

  • Isoflavones can be beneficial at a certain dose but may have adverse effects if overconsumed.
  • Extreme examples like consuming three liters of soy milk are not informative because they exceed safe limits for calcium intake.
  • Intervention studies with high amounts of isoflavones (found in six to eight servings of soy) show no adverse effects.
  • Animal studies are not reliable models for understanding the effects of soy on humans; human data should be relied upon.

New Section

This section reassures men about the impact of soy consumption on erections, penis size, and gynecomastia (man boobs).

Effects on Male Health

  • Consuming up to four servings of soy per day does not affect erections, penis size, or gynecomastia.
  • A three-year study providing four servings' worth of isoflavones from soy showed no evidence of breast swelling or other adverse effects.
  • Clinical trials and meta-analyses have found no adverse effects on sperm, semen, testosterone, or estrogen levels.

New Section

This section discusses the benefits of soy in promoting muscle growth and strength.

Soy and Muscle Building

  • A meta-analysis of nine clinical studies showed that soy promotes muscle mass and strength gains similar to animal protein and whey protein.
  • The consensus is that the amount of protein consumed is more important than the type of protein for building muscle.
  • Even proponents of animal protein have changed their views based on emerging data.

New Section

This section addresses the controversy surrounding soy consumption and the role of groups like Western A Price Foundation.

Controversy Surrounding Soy

  • Western A Price Foundation was active in raising concerns about soy but has become less vocal over time.
  • Animal studies are not dismissed but are used for hypothesis generation rather than determining human health outcomes.
  • Initially, there were scientific inaccuracies in some claims made by Western A Price Foundation regarding soy.
  • The speaker acknowledges the importance of animal studies but emphasizes relying on human data for accurate conclusions.

New Section

This section discusses the impact of soy on breast cancer and highlights the importance of human studies over animal studies.

Soy and Breast Cancer

  • In the late 1990s, a laboratory at the University of Illinois found that implanting human breast cancer cells into mice and giving them isoflavones (found in soy) stimulated tumor growth in estrogen-sensitive tumors.
  • However, 13 clinical studies have shown that soy does not increase or affect breast tissue density, which is a marker of breast cancer risk.
  • Six clinical studies conducted biopsies before and after exposure to isoflavones or soy and found no adverse effects.
  • Observational studies suggest that women who consume soy after a breast cancer diagnosis actually benefit from doing so.
  • A recent study from Korea showed that fermented soy consumption reduced recurrence of breast cancer.

New Section

This section emphasizes the limitations of animal studies in predicting effects in humans and discusses the variability in outcomes based on different types of breast cancer.

Limitations of Animal Studies

  • Animal studies are often relied upon when there are no human studies available, but they may not be good predictors of effects in humans.
  • Some scientific articles make definitive statements based on animal studies without highlighting this limitation.

Variability in Outcomes

  • The effect of soy on breast cancer recurrence and risk reduction varies depending on the type of breast cancer.
  • Some papers show better effects in women with estrogen receptor-positive tumors, while others show similar effects regardless of estrogen receptor status.
  • The mechanism behind these varying outcomes is not clear.

New Section

This section provides an overview of soy isoflavones (phytoestrogens) and their distribution in nature. It also explains their chemical structure and their binding to estrogen receptors.

Soy Isoflavones

  • Isoflavones are diphenolic compounds found in various foods, with soybeans being the most commonly consumed source.
  • In Japan, typical isoflavone intake is around 30 to 40 milligrams per day, while in the U.S it is fewer than three milligrams per day.
  • Isoflavones have a chemical structure similar to estrogen and can bind to estrogen receptors.
  • There are two types of estrogen receptors: estrogen receptor Alpha and estrogen receptor Beta.
  • Isoflavones have more affinity for estrogen receptor Beta, which has an anti-proliferative effect. Estrogen receptor Alpha has a proliferative effect.

New Section

This section discusses the differentiation between isoflavones and estrogen at the molecular level based on their binding preferences to different estrogen receptors.

Binding Preferences

  • Isoflavones preferentially bind to estrogen receptor Beta rather than estrogen receptor Alpha.
  • Activating estrogen receptor Beta tends to have an anti-proliferative effect.
  • Binding to estrogen receptor Alpha has more of a proliferative effect.
  • The interaction between compounds that bind to these receptors can influence their effects.

The transcript does not provide timestamps for the remaining content.

New Section

This section discusses the benefits of consuming soy after a breast cancer diagnosis and addresses the safety of soy for breast cancer patients.

Benefits of Consuming Soy After Breast Cancer Diagnosis

  • Studies show that consuming soy after a breast cancer diagnosis is beneficial.
  • Five intervention studies or observation additional studies have shown this association.
  • At least 10 scientific organizations, including the Irish Society of Oncology, Canadian Cancer Society, and American Cancer Society, have concluded that soy is safe for breast cancer patients.

Need for Clinical Trial

  • It would be ideal to conduct a clinical trial comparing breast cancer patients who consume soy with those who consume a control protein (such as animal protein).
  • The study would examine recurrence and mortality over a five or six-year period to definitively address the question of soy's impact on breast cancer outcomes.
  • However, such a study has not been conducted yet.

Nutritional Value of Soy

  • Soy is not just a source of isoflavones but also provides other nutritional benefits.
  • It is a high-quality protein with good protein digestibility and amino acid score.
  • Full-fat soy foods contain omega-3 fatty acids and linoleic acid.
  • Soy also contains B vitamins.

FDA Health Claim for Soy Protein and Cholesterol

  • In 1999, the U.S. Food and Drug Administration (FDA) approved a health claim for soy foods and coronary heart disease based on the cholesterol-lowering effect of soy protein.
  • Several meta-analyses have shown statistically significant reductions in LDL cholesterol levels due to soy protein consumption.
  • The FDA has delayed their decision about the health claim since 2017, but currently, it can still be stated that soy protein lowers cholesterol levels.

Importance of Replacement Nutrient

  • When replacing saturated fat in the diet, the choice of replacement nutrient matters.
  • Replacing saturated fat with refined carbohydrates may increase the risk, while replacing it with polyunsaturated and monounsaturated fats decreases the risk of cardiovascular disease.

New Section

This section provides an overview of the history and current status of the FDA health claim for soy protein and its impact on cholesterol levels.

History of FDA Health Claim for Soy Protein

  • The FDA approved a health claim for soy foods and coronary heart disease in 1999 based on the cholesterol-lowering effect of soy protein.
  • In December 2007, the FDA announced that they would re-evaluate the evidence supporting this health claim.
  • They intimated that they might revoke the health claim due to inconsistent data.

Current Status of FDA Health Claim

  • Since 2017, the FDA has delayed their decision about revoking or modifying the health claim.
  • Meta-analyses have shown a statistically significant reduction in LDL cholesterol levels due to soy protein consumption.
  • The final decision by the FDA is still pending, and it is uncertain what conclusion they will reach regarding the health claim.

Variability in Nutrition Studies

  • Nutrition studies often show variability due to factors such as sample size, duration, age, gender, and background diet.
  • Small sample sizes and short durations can contribute to inconsistent results.

Benefits of Soy Consumption Beyond Health Claims

  • Consuming soy as a replacement for animal protein can provide benefits beyond specific health claims.
  • It helps reduce intake of iron and saturated fat from animal sources.
  • The change in fatty acid content and protein content contributes to overall improved nutrition.

New Section

In this section, the speaker discusses the impact of saturated fat on the risk of heart disease and addresses misconceptions about soy as an endocrine disruptor.

Impact of Saturated Fat on Heart Disease Risk

  • The speaker mentions that they cannot comment in detail on the relationship between saturated fat and heart disease as it is outside their area of expertise. However, they highlight that the food matrix may affect how saturated fat actually affects the risk of heart disease.

Misconceptions about Soy as an Endocrine Disruptor

  • The speaker acknowledges a previous episode with Dr. Jill Carvalho where they discussed the topic in detail. They mention that there is misinformation regarding soy being an endocrine disruptor and highlight that recent articles now emphasize that soy is not harmful to breast cancer patients or high-risk women.
  • The speaker refers to a paper with 30,000 words and 700 references which concluded that neither soy nor isoflavones warrant classification as endocrine disruptors. They explain that most information suggesting soy as an endocrine disruptor is based on animal studies, whereas clinical studies have shown no adverse effects in humans.
  • The speaker mentions a hypothesis proposed by Cam Satchel in 2002, suggesting that individuals who host intestinal bacteria capable of converting certain compounds in soy into beneficial substances may benefit from consuming soy. However, further clinical studies are needed to confirm this hypothesis.

New Section

In this section, the speaker discusses the metabolism and absorption of soy isoflavones and highlights bioindividuality when it comes to their effects.

Metabolism and Absorption of Soy Isoflavones

  • The speaker explains that soy isoflavones, like many phenolic compounds, are not well absorbed in the small intestine. Instead, they make their way to the colon where they can be reabsorbed to some extent. They mention that soy may have prebiotic effects due to the presence of oligosaccharides that reach the colon.
  • The speaker mentions a hypothesis proposed by Cam Satchel in 2002, suggesting that individuals who host intestinal bacteria capable of converting certain compounds in soy into beneficial substances may benefit from consuming soy. However, further clinical studies are needed to confirm this hypothesis.
  • It is noted that there is significant bioindividuality when it comes to the metabolism of isoflavones. Even if a group of people consumes the same amount of isoflavones, their blood levels will vary greatly.

The transcript provided does not contain enough content for additional sections at this time.

New Section

The speaker discusses the classification of soy-based foods and their potential health benefits.

Should Soy Foods be Part of a Healthful Diet?

  • The speaker expresses their personal preference for soy burgers and soy milk, despite them being classified as ultra-processed foods.
  • They argue that not all ultra-processed foods should be grouped together, as soy burgers are different from unhealthy snacks like Twinkies or corn chips.
  • The speaker mentions that the processing of soy can reduce its isoflavone content, contrary to popular belief that processed forms are more concentrated sources of isoflavones.

Isoflavone Content in Different Soy Foods

  • Traditional soy foods like tofu and edamame contain approximately 3-4 milligrams of isoflavones per gram of protein.
  • A cup of soy milk with 7-8 grams of protein provides around 25 milligrams of isoflavones.
  • In Japan, the average daily intake of isoflavones among older men and women is about 40 milligrams, equivalent to one and a half servings per day on average.

Concentrated Sources of Protein vs. Traditional Soy Foods

  • Concentrated sources like soy protein isolate and concentrate have lower levels of isoflavones compared to traditional soy foods.
  • Soy protein isolate typically contains only 10-20% of the isoflavone content found in traditional soy foods when expressed on a milligram for gram protein basis.

Clinical Studies and Use of Concentrated Soy Protein

  • Most clinical studies use concentrated sources like soy protein isolate or concentrate due to ease of consumption in Western populations.
  • These products have shown a reduction in LDL cholesterol levels in clinical trials.

New Section

The speaker addresses concerns about isoflavones and discusses the isoflavone content in different soy-based products.

Isoflavone Content in Different Soy-Based Products

  • The Impossible Burger contains only 2 milligrams of isoflavones, while a cup of soy milk contains 25 milligrams.
  • If someone has concerns about isoflavones, they should focus on consuming products made with concentrated sources of protein.

Safety and Consumption of Isoflavones

  • The speaker mentions that there is no reason to be concerned about isoflavones as numerous studies support their safety.
  • Regulatory authorities like the FDA and European Food Safety Authority have concluded that isoflavones are safe for consumption.

Use of Concentrated Soy Protein in Clinical Studies

  • Clinical studies often use concentrated sources like soy protein isolate or concentrate due to blinding participants and ease of incorporation into various foods.
  • These concentrated sources have shown a reduction in LDL cholesterol levels in clinical trials.

New Section

The speaker discusses TVP (Textured Vegetable Protein) and its classification as a soy flour product.

TVP as a Soy Flour Product

  • TVP falls under the category of soy flour products.

New Section

In this section, the speaker discusses the controversy surrounding soy formula and its potential effects on infants.

Concerns about Soy Formula

  • There was initially negligible concern about soy formula.
  • The next review stated minimal concern.
  • Observational studies have been conducted on children consuming soy formula, breast milk, or cow's milk formula through 14 years of age.
  • The University of Arkansas is conducting a study in this area and has not found any adverse effects so far.
  • However, studying the impact of soy consumption during infancy is challenging due to ethical limitations.

New Section

In this section, the speaker talks about the prevalence of soy allergy and its comparison to other allergies.

Prevalence of Soy Allergy

  • Food allergy is on the rise globally.
  • There are approximately 160 to 200 foods known to cause allergic reactions in individuals.
  • Soy allergy ranks eighth among the major allergens responsible for food allergic reactions.
  • Based on surveys conducted in Canada and the U.S., it is estimated that about three out of every 1,000 adults are allergic to soy.
  • Soy is present in many Western foods as an ingredient but in very small amounts that do not contribute significantly to nutrition.
  • Approximately 70% of children outgrow their soy allergy by age 10.

New Section

This section focuses on how pea protein has gained popularity as an alternative to soy protein due to its exclusion from major allergen lists.

Pea Protein as an Alternative

  • Pea protein has become popular because it is currently not included in major allergen lists like soy protein.
  • Reports suggest an increasing incidence of allergy to pea protein, which may lead to its inclusion in allergen lists in the future.
  • Soybean oil, often labeled as vegetable oil in the United States, does not cause allergic reactions in individuals allergic to soy protein.
  • Soybean oil contains essential fatty acids omega-6 linoleic acid and omega-3 linolenic acid.

New Section

The speaker discusses the historical concerns and current understanding of how soy isoflavones may interact with thyroid hormone production and function.

Soy Isoflavones and Thyroid Health

  • In the late 1950s and early 1960s, there were instances of thyroid problems in infants fed soy formula fortified with iodine.
  • A research group in the late 1990s and early 2000s raised concerns about isoflavones inhibiting an enzyme involved in thyroid hormone synthesis.
  • However, subsequent studies have provided a more nuanced understanding of this interaction.

The transcript does not provide further information on this topic.

Effect of Soy or Isoflavones on Breast Cancer Risk

This section discusses the potential effect of soy or isoflavones on reducing the risk of developing breast cancer, particularly when consumed during childhood and teenage years.

Soy Consumption in Childhood and Teenage Years

  • Observational studies suggest that consuming soy during childhood and teenage years may reduce the risk of developing breast cancer later in life.
  • Isoflavones found in soy are believed to affect the cells in the developing breast, making them less likely to transform into cancer cells.
  • Observational studies show a 25% to 50% reduction in breast cancer risk associated with soy consumption.
  • It is recommended that all girls consume at least one serving of soy per day to potentially derive this benefit.

Observational Studies Comparing Asian Populations

  • The observational evidence compares women who consume soy early in life in Asia with Western populations.
  • These studies examine incidents of breast cancer among different populations and their soy consumption habits.
  • The focus is on comparing women within a population who consume soy early in life versus those who do not.

Challenges with Observational Studies

  • Conducting observational studies on the effects of soy consumption early in life can be challenging due to recall bias.
  • Asking older women to recall their soy consumption during childhood may lead to inaccuracies.
  • Some studies also rely on mothers' recollection of their daughters' soy consumption.

Research on Soy and Health Outcomes

This section discusses research conducted on various health outcomes related to soy consumption, including its potential impact on migraines and depression.

Research from Iran

  • Iranian researchers have published a significant amount of research on soy, despite not being a major consumer or producer of soybeans.
  • A study from Iran examined the association between soy isoflavon consumption and migraines.
  • Another study suggested an inverse association between soy consumption and depression.

Observational Studies on Soy and Health Outcomes

  • Observational epidemiological studies are commonly conducted to investigate the effects of soy on various health outcomes.
  • Recent studies from the United States compare different levels of soy consumption, often comparing low or no soy intake with higher intakes.
  • Prospective studies, which carry more weight among epidemiologists, are preferred for evaluating the potential health effects of soy.

Importance of Prospective Studies and Asian Cohorts

This section emphasizes the importance of prospective studies and Asian cohorts in evaluating the potential health effects of soy due to their sufficient intake levels.

Prospective Studies vs. Observational Studies

  • Prospective studies are considered more reliable than observational studies when evaluating the impact of soy on health outcomes.
  • Observational studies may still find associations even with low levels of soy intake, but they may not have significant health effects.

Asian Cohorts and Vegetarian Cohorts

  • Asian cohorts and vegetarian cohorts like EPIC Oxford or The Seventh-Day Adventist Adventist Health Study 2 provide valuable data for studying the health effects of soy.
  • These populations have a higher level of soy consumption, making it biologically plausible to observe potential health benefits associated with soy intake.

The transcript does not provide additional sections or timestamps beyond this point.

Limiting Serving Size

The speaker discusses the importance of consuming no more than one serving per meal.

Importance of Limiting Serving Size

  • It is crucial to limit the serving size consumed per meal.
  • Consuming excessive servings can lead to overeating and weight gain.
  • Portion control plays a significant role in maintaining a healthy diet.
  • By limiting serving sizes, individuals can better manage their calorie intake.
Video description

Soy foods have proved to be a contentious topic for decades now. With some dietary camps claiming the dangers of soy and others promoting its boundless benefits, it’s natural to be hesitant about consuming this product. 👇 Visit The Proof website for supporting studies and the full show notes 👇 https://theproof.com/podcast/ In Episode #258, I sit down with Dr Mark Messina for a deep dive into the safety and potential benefits of soy consumption. We clear the air on this plant food, evaluating what the science actually says and defining how to healthily consume it. Dr Mark Messina is the Director of Nutrition Science and Research for Soy Nutrition Institute Global, co-owner of Nutrition Matters, Inc., and an adjunct associate professor at Loma Linda University. With over 30 years of experience, Dr Messina has dedicated his career to studying the health effects of soy foods and soybean components, including isoflavones. He has published over 100 articles and book chapters and given more than 700 presentations in 55 countries. Dr Messina is also the chairperson of the editorial advisory board for The Soy Connection and has organised and chaired numerous international symposia on soy's role in preventing and treating chronic disease. He is the co-author of three books on soy, vegetarianism, and navigating vegetarian diets from a health perspective. In this conversation, Dr. Messina tackles common concerns and misconceptions about soy, addressing its safety in relation to male feminisation, breast cancer, thyroid function, and dosage. We dive deep into isoflavones, with Dr. Messina explaining how they differ from oestrogen. An interesting fact to remember is that traditional Asian soy foods contain about 3–4 mg of isoflavones per gram of protein. In contrast, soy protein isolate and soy protein concentrate are typically processed in a way that results in a loss of approximately 80–90% of the isoflavone content. Soy flour and textured vegetable protein (TVP) made from soy flour retain the full complement of isoflavones, maintaining the same isoflavone (mg) to protein (g) ratio found in soybeans and traditional Asian soy foods. This episode is brimming with essential information to help you comprehend the health and safety aspects of soy. Specifically, we discuss: 00:00 - Intro 01:45 - Soy throughout history 6:12 - Dr. Mark Messina and the Soy Nutrition Institute 8:04 - Industry affiliation in research 18:02 - Debate surrounding soy and breast cancer 24:04 - Isoflavones and oestrogen 32:12 - Isoflavones, breast tissue and cholesterol 40:39 - Oversimplification of health information  48:31 - Fermented soy and equol  53:36 - How much isoflavones are in your soy foods? 59:12 - Safe upper limit of soy isoflavones intake per day 1:01:58 - Are blood tests necessary for high protein eaters? 1:04:10 - Soy formula and soy allergy 1:11:34 - Soy and thyroid Health 1:16:44 - Does soy affect menstrual cycle length?  1:23:26 - Soy consumption and migraines 1:27:43 - Isoflavonoid supplements 1:29:40 - Soy farming and the environment 1:33:42 - Outro I hope this conversation leaves you feeling more confident in your choices regarding soy. With decades of research and experience, Dr. Messina brings clarity to the soy debate in Episode #258, putting controversies to rest once and for all. Connect: - To stay up to date with Dr Mark Messina’s work, head to https://sniglobal.org/ - Read Dr Messina’s recent, relevant articles in the full show notes If you have any additional questions you would like answered in the future, let me know in the comments. The best way to support the show is to use the products and services offered by our sponsors. To check them out, and enjoy great savings, visit theproof.com/friends. Enjoy, friends. Simon ==== Want to support the show? The best way to support the show is to use the products and services offered by our sponsors. To check them out, and enjoy great savings, visit https://theproof.com/friends/. • The Proof with Simon Hill - https://theproof.com/podcast/ • Book: The Proof is in the Plants - https://theproof.com/book/ • Apple Podcast - https://podcasts.apple.com/gb/podcast/the-proof-with-simonhill/id1367773989 • Spotify - https://open.spotify.com/show/7bAIJCVgnquxXZuQCdZyTi • Instagram - https://www.instagram.com/theproof/ • Twitter - https://twitter.com/theproof • Facebook - https://www.facebook.com/theproofwithsimonhill • Plant-Based Ferments Guide - https://theproof.com/ferments/ • Two week meal plan - https://theproof.com/mealplan/ • Plant Performance - https://theproof.com/plant-performance/ • Use the products and services offered by our sponsors. To check them out, and enjoy great savings, visit theproof.com/friends.