The Carnivore Diet

Researched & Written By: Dr. Jessica, PharmD

Introduction

Primal Queen is set out to design a line of supplements that could fit in and add to the Carnivore Diet and to dispel the many myths and rumors surrounding the diet itself. Yes, as a safe rule, dietary variety is commonly recommended in National Guidelines to meet all nutritional needs. That does not mean that restrictive diets, such as the Carnivore Diet, do not meet all your dietary needs though. It just means that education and awareness are lacking regarding innovative, but also historic, ways of doing things.^1,2

Restrictive diets have been touted for both health and philosophical reasons with veganism being one of the most popular in modern history. It has been studied for health benefits related to reduction in body mass index, improvement in serum lipids (cholesterol), and cancer prevention. With this diet however, negative effects have also been reported as dieters lack vitamin B12, calcium, and a solid and reliable source of protein. These deficiencies have been linked to an increased incidence of bone fractures.^3-5

New interest has grown in an opposite, and dare I say, superior eating pattern, the Carnivore Diet, which eliminates most or all plant-based foods. These diets high in animal foods have been historically discouraged based on fears of high saturated fats content and low density of essential nutrients and bioactive compounds such as fiber. Evidence about the health status of people consistently following a carnivore eating pattern is showing its health benefits and previous beliefs are being dispelled rapidly.⁶

The Carnivorous Cavewomen?

The carnivorous cavewomen led a solitary and nomadic lifestyle on the vast Eurasian steppe. Since there were no cereals like Weetabix available at that time and edible plants were scarce, the carnivorous cavewomen had no choice but to rely on meat as a source of nutrition. Fortunately, meat was abundant and provided the perfect fuel for human biochemistry. With a diet rich in meat, the carnivorous cavewomen was able to survive the harsh winters of the paleolithic wilderness, pass on her genes to future generations, and potentially live into her 70s. She had plenty of leisure time, a strong and athletic physique, and no risk of developing diabetes. In comparison to the neolithic farmer who came after her, the cavewomen lived a fulfilling life and would have likely won in a physical competition. However, the farmer may have had more descendants present at his deathbed. The consumption of carnivorous diets has a long history dating back to the beginning of Homo sapiens and even earlier in the Homo genus. Throughout the stone age, the vast steppe, the forests of Germany, and the freezing Arctic, people have consistently survived off of a carnivore diet.

Although we cannot return to the hunter-gatherer lifestyle, we can incorporate the natural wisdom of how humans evolved to eat into our modern lives. Our modern lifestyles and diets are artificial compared to the environment in which we evolved for hundreds of thousands of years. When we consider both historical evidence and contemporary medical data, it becomes clear that we are not doing a good job of taking care of ourselves as a species. By looking back at our dietary evolution, we can learn how to better care for ourselves, starting with the food we eat. Animal meat is the foundation of a diet that humans are evolved to thrive on.

What is the Carnivore Diet? ⁷

The Carnivore Diet is a way of eating that focuses on consuming animal-sourced foods (ASFs) and avoids plant-based foods. Some people with autoimmune disorders may follow this diet because it can offer immunological benefits. Since ASFs are low in carbohydrates and high in fat, the Carnivore Diet is often ketogenic, meaning it can help the body enter a state of ketosis. This diet can include various types of meats, including lean and fatty cuts, as well as organ meats. The meats can be cooked in different ways, such as boiling or consuming them raw, and how the meat is prepared can affect the nutrients it provides.

What are the benefits of a carnivore diet? ^7-9

Harvard University researchers Dr. Belinda Lennerz and Dr. David Ludwig have conducted the first study on the effects of an all-meat diet on 2,029 people over a 6-month period. Their research found that "adults consuming a carnivore diet experienced few adverse effects and instead reported health benefits and high satisfaction." The diet led to positive health outcomes such as:

• 93% improved or resolved obesity and excess weight
• 93% improved hypertension
• 98% improved conditions related to diabetes
• 97% improved gastrointestinal symptoms
• 96% improved psychiatric symptoms

It's important to keep in mind that the data in this study is based on self-reports, which means it can only show a correlation, not a causal relationship, and may not be completely reliable. However, the findings are significant and suggest that an all-meat diet can be healthy.

Organ meats are some of the most nutritious superfoods in nature. They are typically much higher in a variety of essential nutrients than muscle meat. The various highly concentrated nutrients in organ meats allow you to create specific blends to meet your health needs. You can think of organ meats as nature's original multivitamin. The benefits of consuming meat become evident when you consider the roles of the various nutrients that are most prevalent and/or only found in meat. Here are some examples: fertility boosting, weight loss, anti-aging, antioxidant effects, gene expression, mood enhancement, stimulated stem cell production, immune function, and increase in production of human growth hormone.

Let’s examine the specific nutrients found in meat and how they contribute to the benefits of consuming it.

Vitamin A^10-12

Vitamin A, which comes from the liver, is necessary for the proper functioning of over 500 genes and is crucial for the growth of stem cells. Additionally, the type of vitamin A found in animal-based foods is more easily utilized by the body compared to the beta carotene found in plant-based sources.

B Vitamins^13-15

The B vitamins found in meat and kidney, play a vital role in maintaining the body's overall health and wellbeing. These vitamins are responsible for converting food into energy, producing red blood cells that transport oxygen to the brain, and enhancing cognitive function and emotional stability. B12 is mostly found in animal-based products such as meat and dairy.

Vitamin K2^16-17

Vitamin K2, found in bones, liver and cartilage, plays an important role in maintaining bone and brain health. This vitamin regulates the amount of calcium in the bones, promotes the growth of stem cells in the bone marrow and helps prevent heart disease. Not having enough K2 can be linked to Alzheimer's disease.

Choline^18-19

Choline, which can be found in liver and kidneys, is vital for the proper functioning of various bodily processes. It plays a role in maintaining the structure of cells, producing molecules involved in cell signaling, breaking down fats and eliminating cholesterol from the liver. Without adequate choline intake, cognitive function may be impaired, including issues with memory and focus. While the body produces a limited amount of choline, the primary source of it is meat.

Heme Iron^20-21

Heme iron, a type of iron that is unique to red meat and can be found in organ meats such as kidney, liver, and heart, is critical for various bodily functions. Iron is necessary for the production of red blood cells, providing energy, promoting a healthy immune system and supporting cognitive health.

Copper²²

Copper, which comes from liver, plays a crucial role in various bodily processes. It is necessary for producing energy, keeping blood vessels healthy and constructing connective tissues. Copper also has an important role in immune system function, maintaining nervous system health, activating genes, promoting brain development, regulating hormone metabolism and contributing to fertility.

Zinc^23-25

Organs such as liver, kidney, and heart, is a rich source of zinc, which is more easily absorbed by the body compared to zinc found in grains. Zinc is vital for maintaining a healthy immune system, assisting the body in protein and DNA production, promoting wound healing, contributing to growth and development during childhood and has antioxidant effects.

Carnosine^26-27

Carnosine, a beneficial anti-aging substance that is only found in meat, particularly in heart and liver, is present in high amounts in the heart, brain, and muscles, where it works to prevent damage and deterioration. It also works to inhibit the harmful process of glycation, which occurs when glucose attaches to cells and DNA. Carnosine acts as a powerful antioxidant that guards against damage and protects the telomeres from shortening.

Carnitine^28-30

Carnitine, which is primarily found in meat, particularly in kidney and liver, is essential for enhancing male fertility, fighting off anemia, especially when combined with kidney dysfunction. Research has also demonstrated it could have significant effects on mitochondria function, and insulin sensitivity for those with type 2 diabetes and can also prevent damage to the heart muscle caused by poor blood flow in heart attack patients.

Creatine^31-33

Creatine, which is found exclusively in meat, particularly in liver and kidneys, is a widely used supplement among athletes and weightlifters. Studies have found that vegetarians who take creatine supplements see an improvement in cognitive function, and both vegetarians and those who eat meat see improved athletic performance when using it. Low levels of creatine have been found in Alzheimer's patients and studies have shown that it can also enhance cardiovascular function in heart failure patients. Additionally, when combined with exercise, creatine supplementation can help improve blood sugar control for people with type 2 diabetes.

Taurine^34-36

Taurine, an effective antioxidant that can be found in heart and reproductive organs of animals, helps to reduce the harmful effects of glycation, inflammation, and oxidative stress. It might also have an antidepressant effect, which could be the reason why some people feel good after consuming meat.

Does the Carnivore Diet Lack Fiber?!^38-40

You may have heard the myth that you need fiber in your diet, but modern research on the effects of fiber suggests that it is not necessary and we may be better off without it. A 2012 study published in the World Journal of Gastroenterology found that "Our study shows a very strong correlation between improving constipation and its associated symptoms after stopping dietary fiber intake."

Research has revealed that too much insoluble fiber can bind to minerals like iron, zinc, magnesium, and calcium and prevent the body from absorbing them. In addition, insoluble fibers may inhibit digestive enzymes, reducing protein absorption. This means that fiber can actually have a negative impact on nutrient intake.

A 2012 study on the impact of fiber restriction on constipation and irritable bowel syndrome (IBS) found that significant symptom improvement occurred after just two weeks of eliminating fiber from the diet. However, when participants resumed consuming fiber, their IBS symptoms returned. Other studies have also demonstrated that increasing fat intake and decreasing fiber intake can boost testosterone and reduce estrogen levels. One study reported that increasing fat intake and decreasing fiber intake led to a 13% increase in testosterone and a 12-28% decrease in estrogen. Higher testosterone levels may help increase muscle mass.

Is Vitamin C Deficiency a Concern on a Carnivorous Diet?⁴¹

Meat has historically been known to have properties that prevent scurvy, despite being a relatively poor source of Vitamin C. Some scientists suggest that this may be due to the presence of carnitine in meat, which can spare the use of Vitamin C and prevent the early symptoms of scurvy such as fatigue and muscle weakness. However, there is limited research on the specific ways in which this occurs and the extent to which it is effective.

Is a carnivore diet safe?⁴²

Human evolution has been closely tied to the consumption of animals for millions of years. In fact, it is believed that the hunting and eating of animals played a significant role in the development of our large and complex brains. Examination of collagen samples from Neanderthals and Homo sapiens that are over 80,000 years old provides evidence of this. These samples demonstrate that our ancestors had stable nitrogen isotope levels in their bones that exceeded those of other carnivorous animals. This implies that our ancestors consumed a significant amount of animal-based foods. A carnivorous diet, similar to what our ancestors ate may be an advantageous choice for optimal health.

Potential Health Benefits that Organ Meats

An old belief held by traditional cultures, native people and early healers, was that consuming the organs of a healthy animal can strengthen and support the corresponding organ in an individual. For instance, traditional healers used to give the heart of a healthy animal to a person with a weak heart as a treatment. Similarly, it was believed that eating the ovaries, uterus, and fallopian tubes of a healthy animal would support female fertility and optimal health. This principle is referred to as “like supports like”.

Our ancestors recognized the value of organs and glandular as a nutrient-dense superfood and incorporated them in their diet regularly. They believed that consuming these "like-supports-like" nutrients provided fundamental support in harmony with nature. Let’s dive into the major organs that nourish and support optimal female health.

Uterus^43-45

The uterus is a vital and expandable organ in women's reproductive system, serving as the place where the fertilized egg implants and provides structural integrity for the rest of the reproductive system, as well as supporting the bowel, bladder and pelvic bones. This strong muscular organ expands during pregnancy to accommodate the growing fetus and works hard to produce the contractions required for childbirth. The inside of the uterus is lined with a moist mucous membrane called the endometrium. This lining goes through a process called vascularization during a woman's menstrual cycle, in which the blood vessels proliferate, causing the endometrium to become thicker, preparing for pregnancy. If pregnancy does not occur, the top layers of the endometrium and the blood from the vessels will be shed and flow out during menstruation.

In case of pregnancy, the endometrium will become the home for the fertilized egg and eventually develops into the maternal portion of the placenta. Additionally, networks of blood vessels and nerves in the uterus help to direct blood flow to the ovaries and external genitalia, which supports sexual function.

Having adequate amounts of specific vitamins, minerals, enzymes and peptides that support the uterus is necessary to maintain optimal function of the uterus.

Bovine Uterus contains all of these specific nutrients and may:

• Promote the well-being of the cells in the uterus
• Enhance the condition of the uterus's lining
• Alleviate discomfort associated with endometriosis
• Diminish cysts in the uterus
• Support the uterus during post-birth contractions that help it return to its normal size

Fallopian tubes^46-47

On either side of your uterus are two j-shaped tubes called fallopian tubes, which connect your uterus to your ovaries. These tubes are lined with fine, hair-like structures called cilia that help move eggs from the ovaries to the uterus and guide sperm to the eggs. The fallopian tubes have finger-like structures called fimbriae at the end, which help to capture and guide the egg when it is released from the ovary. These tubes play a crucial role in conception as most fertilization takes place in the fallopian tubes. If any part of the fallopian tubes are damaged, such as by surgery or infection, they can become blocked by scar tissue and this can affect fertility and overall function. To support the optimal function of the fallopian tubes, having adequate supply of vitamins, minerals, enzymes, proteins, and peptides that are specific to the fallopian tubes may be beneficial. Bovine Fallopian Tube contains all of these specific nutrients and may:

• Lessen inflammation in the fallopian tubes
• Boost the likelihood of egg fertilization
• Reinforce the health of the cells in the fallopian tubes
• Ease pelvic pain caused by blocked fallopian tubes
• Promote a healthy environment for the microorganisms

Ovaries^48-50

On each side of your uterus, inside your pelvic area, are two small organs called ovaries, which are a crucial part of your reproductive system. They have two main roles:

• They store and mature the immature eggs (primordial germ cells) each month, which are the building blocks of new life, and it is essential that they are healthy.
• They also produce hormones such as estrogen and progesterone, as well as a small amount of testosterone, which enter the bloodstream. When the ovaries are healthy, these hormones are released in balance with each other. These hormones play an important role in ovulation when an egg is released from the ovary. If these hormones are not balanced, it can lead to health issues, infertility, and difficulty in maintaining energy, drive, and mood.

Having enough of the vitamins, minerals, enzymes and peptides that are specific for the ovaries may aid in optimal function of the ovaries. Bovine ovary contains all of these specific nutrients and may:

• Enhance the health of the cells in the ovaries
• Diminish occurrences of acne, cysts and excessive facial hair growth
• Improve mood and symptoms related to premenstrual syndrome
• Regulate menstruation and menstrual flow
• Alleviate menstrual cramps and hot flashes

Heart^51-52

The heart is a small organ about the size of your fist that works to pump blood throughout your body. It is the central organ of the cardiovascular system, which is a network of blood vessels that carries blood all around your body, and helps to regulate your heart rate and blood pressure. The heart is divided into four main sections, or chambers, that are made of muscle and work based on electrical impulses. Your brain and nervous system control the heart's function. When it comes to nutrition, beef heart is an excellent source of many essential nutrients such as zinc, iron, selenium, vitamin B2, vitamin B6, and vitamin B12.Bovine heart contains all of these specific nutrients and may:

• Provides a boost in energy
• Offers protection for the heart
• Improves overall mood
• Strengthens immunity

Kidney^53-55

Our kidneys are vital organs that play an essential role in keeping our bodies in balance. They help to remove waste and toxins, as well as excess water from the bloodstream, which is eliminated from the body through urine. They also help to produce hormones, create red blood cells and convert vitamin D into its active form so that it can be used by the body. Beef kidney is an organ meat that is particularly rich in vitamin B12, selenium, and heme iron, and also contains decent amounts of copper and zinc. Some believe that consuming organ meats like kidney can have "like-supports-like" properties and can promote the health of the kidneys. The nutritional profile of beef kidney may have a positive impact on a variety of bodily functions such as:

• Assist natural reproductive capability
• Enhance eyesight
• Boost energy levels
• Support growth and maturation
• Offer specific benefits to the kidney

Liver^56-57

The liver is located in the upper right side of the abdominal cavity, below the diaphragm, and above the stomach, right kidney and intestines. It plays a critical role in regulating the chemical levels in the blood and producing a substance called bile, which helps to remove waste products from the liver. The blood that comes from the stomach and intestines flows through the liver, and it's responsible for processing this blood by breaking down, balancing, creating nutrients and also changes the form of drugs so that they can be more easily used by the rest of the body or so they become non-toxic. Bovine liver contains a variety of micronutrients and may:

• Enhances energy level
• Maintains overall well-being
• Improves liver function
• Improves liver's blood flow
• Enhances athletic performance
• Offers protection to the liver (hepatoprotection)

Conclusion:

The Carnivore Diet is a unique way to reconnect with our ancestral eating habits and apply them to the modern world. This diet is based on consuming only animal products, which may seem extreme to some, but it has been found to offer a variety of health benefits.

One of the main benefits of the Carnivore Diet is that it is rich in essential vitamins and minerals that are often lacking in other restrictive diets. Organ meats in particular are very nutrient-dense and are a great source of B-vitamins, zinc, and iron, which are all important for the overall health and well-being. For women, consuming organ meats may have additional benefits, such as supporting the health of the ovaries, uterus and fallopian tubes, reducing cramps, hot flashes, and improving chances of pregnancy.

There are few restrictions and you can eat a wide variety of foods, including meat, fish, eggs, and dairy. This eliminates the need to count calories, limit portion sizes or feel guilty about eating certain foods.

The Carnivore Diet has been found to have a positive impact on energy levels, physical performance, and mental clarity.

Overall, while the Carnivore Diet may not be the right choice for everyone, it offers an interesting and potentially beneficial way of eating for modern, optimized living. Its focus on nutrient-dense organ meats and lack of restrictions make it a viable option for those looking to improve their health and well-being.

*Disclaimer:

The information contained in this document is a review of publicly available data and does not constitute claims made regarding any commercially available product nor qualified health benefits with the FDA.

Resources:

• Forsythe, C. E., Phinney, S. D., Fernandez, M. L., Quann, E. E., Wood, R. J., Bibus, D. M., … & Volek, J. S. (2008). Comparison of low fat and low carbohydrate diets on circulating fatty acid composition and markers of inflammation. Lipids, 43(1), 65-77. 
• Theuwissen, E., Smit, E., & Vermeer, C. (2012). The role of vitamin K in soft-tissue calcification. Advances in Nutrition, 3(2), 166-173.
• Yu, Z., Nan, F., Wang, L. Y., Jiang, H., Chen, W., & Jiang, Y. (2020). Effects of high-protein diet on glycemic control, insulin resistance and blood pressure in type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials. Clinical Nutrition, 39(6), 1724-1734.
• Brand-Miller, J. C., Griffin, H. J., & Colagiuri, S. (2012). The carnivore connection hypothesis: revisited. Journal of obesity, 2012.
• Mohorko, N., ÄŒernelič-Bizjak, M., Poklar-Vatovec, T., Grom, G., Kenig, S., Petelin, A., & Jenko-Pražnikar, Z. (2019). Weight loss, improved physical performance, cognitive function, eating behavior, and metabolic profile in a 12-week ketogenic diet in obese adults. Nutrition research, 62, 64-77. https://pubmed.ncbi.nlm.nih.gov/30803508/
• Westerterp-Plantenga, M. S., Lemmens, S. G., & Westerterp, K. R. (2012). Dietary protein–its role in satiety, energetics, weight loss and health. British journal of nutrition, 108(S2), S105-S112.
• Lennerz, B. S., Mey, J. T., Henn, O. H., & Ludwig, D. S. (2021). Behavioral characteristics and self-reported health status among 2029 adults consuming a “carnivore diet.” Current Developments in Nutrition, 5(12). https://doi.org/10.1093/cdn/nzab133
• Tong TYN, Appleby PN, Armstrong MEG, Fensom GK, Knuppel A, Papier K, Perez-Cornago A, Travis RC, Key TJ. Vegetarian and vegan diets and risks of total and site-specific fractures: results from the prospective EPIC-Oxford study. BMC Med 2020;18(1):353.
• Barnard ND, Leroy F. Children and adults should avoid consuming animal products to reduce risk for chronic disease: YES. Am J Clin Nutr 2020;112(4):926–30.
• Reboul, Emmanuelle. “Absorption of Vitamin A and Carotenoids by the Enterocyte: Focus on Transport Proteins.” Nutrients, U.S. National Library of Medicine, 12 Sept. 2013, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3798921/#:~:text=Retinol%20absorption%20efficiency%20ranges%20between,43%2C44%2C45%5D.
• Reboul E., Richelle M., Perrot E., Desmoulins-Malezet C., Pirisi V., Borel P. Bioaccessibility of carotenoids and vitamin E from their main dietary sources. J. Agric. Food Chem. 2006;54:8749–8755. doi: 10.1021/jf061818s.
• Dhuique-Mayer C., Borel P., Reboul E., Caporiccio B., Besancon P., Amiot M.J. Beta-cryptoxanthin from citrus juices: Assessment of bioaccessibility using an in vitro digestion/Caco-2 cell culture model. Br. J. Nutr. 2007;97:883–890. doi: 10.1017/S0007114507670822.
• The effects of vitamin B in depression. Mikkelsen K, Stojanovska L, Apostolopoulos V. Curr Med Chem. 2016;23:4317–4337. 
• The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: a review of literature. Pawlak R, Lester SE, Babatunde T. Eur J Clin Nutr. 2014;68:541–548. 
• High vitamin B12 level and good treatment outcome may be associated in major depressive disorder. Hintikka J, Tolmunen T, Tanskanen A, Viinamäki H. BMC Psychiatry. 2003;3:17. 
• Ducy P, Desbois C, Boyce B, Pinero G, Story B, Dunstan C, Smith E, Bonadio J, Goldstein S, Gundberg C, et al. Increased bone formation in osteocalcin-deficient mice. Nature. 1996;382:448–52.
• Price PA, Toroian D, Lim JE. Mineralization by inhibitor exclusion: the calcification of collagen with fetuin. J Biol Chem. 2009;284:17092–101.
• Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B-6, Vitamin B012, Pantothenic Acid, Biotin, and Choline. Washington, D.C.: National Academy of Sciences; 1998. pp. 390–422.
• Penry J, Manore M. Choline: an important micronutirent for maximal endurance-exercise performance? Int J Sport Nutr Exerc Metab. 2008;18:191–203. 
• Waldmann A, Koschizke W, Leitzman C, Hahn A. Dietary iron intake and iron status of German female vegans: results of the German vegan study. Ann Nutr Metab. 2004;48:103-108.
• Shenkin A. Dietary reference values for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium and zinc. Journal of Human Nutrition and Dietetics. 2003;16(3):199-200. doi:10.1046/j.1365-277x.2003.00439.x
• “Office of Dietary Supplements - Copper.” Copper - Health Professional Fact Sheet, 18 Oct. 2022, ods.od.nih.gov/factsheets/Copper-HealthProfessional.
• Khan MS, Zaman S, Sajjad M, Shoaib M, Gilani G. Assessment of the level of trace element zinc in seminal plasma of males and evaluation of its role in male infertility. Int J Appl Basic Med Res. 2011;1 (2):93–6.
• an M, Hardin K, Ho E. Differential response to zinc-induced apoptosis in benign prostate hyperplasia and prostate cancer cells. J Nutr Biochem. 2010; 21(8):687–94.
• Yamaguchi S, Miura C, Kikuchi K, Celino FT, Agusa T, Tanabe S, et al. Zinc is an essential trace element for spermatogenesis. Proc Natl Acad Sci USA. 2009;106(26):10859–64.
• Y.J. Park, S.L. Volpe, E.A. Decker, Quantitation of carnosine in humans plasma after dietary consumption of beef. J. Agric. Food Chem., 53, (2005), 4736– 4739.
• L.M. Maynard, G.A. Boissonneault, C.K. Chow, G.G. Bruckner, High levels of dietary carnosine are associated with increased concentrations of carnosine and histidine in rat soleus muscle. J. Nutr., 131, (2001), 287– 290.
• Aliabadi E, Soleimani Mehranjani M, Borzoei Z, Talaei-Khozani T, Mirkhani H, Tabesh H.2012. Effects of L-carnitine and L-acetyl-carnitine on testicular sperm motility and chromatin quality. Iranian Journal of Reproductive Medicine 10 77–82.
• Balercia G, Regoli F, Armeni T, Koverech A, Mantero F, Boscaro M.2005. Placebo-controlled double-blind randomized trial on the use of L-carnitine, L-acetylcarnitine, or combined L-carnitine and L-acetylcarnitine in men with idiopathic asthenozoospermia. Fertility and Sterility 84 662–6. ( 10.1016/j.fertnstert.2005.03.064)
• Banihani S, Agarwal A, Sharma R, Bayachou M.2014. Cryoprotective effect of L-carnitine on motility, vitality and DNA oxidation of human spermatozoa. Andrologia 46 637–6. ( 10.1111/and.12130)
• Dolan E., Artioli G.G., Pereira R.M.R., Gualano B. Muscular Atrophy and Sarcopenia in the Elderly: Is There a Role for Creatine Supplementation? Biomolecules. 2019;9:642. doi: 10.3390/biom9110642.
• Dolan E., Gualano B., Rawson E.S. Beyond muscle: The effects of creatine supplementation on brain creatine, cognitive processing, and traumatic brain injury. Eur. J. Sport Sci. 2019;19:1–14. doi: 10.1080/17461391.2018.1500644.
• Wallimann T., Turner D.C., Eppenberger H.M. Localization of creatine kinase isoenzymes in myofibrils. I. Chicken skeletal muscle. J. Cell Biol. 1977;75:297–317. doi: 10.1083/jcb.75.2.297.
• Kim SJ, Lee HW and Gupta RC: Taurine, Bone growth and bone development. Curr Nutr Food Sci. 4:135–144. 2008.
• Aerts L and Van Assche FA: Taurine and taurine-deficiency in the perinatal period. J Perinat Med. 30:281–286. 2002.
• Chesney RW: Taurine: Its biological role and clinical implications. Adv Pediatr. 32:1–42. 1985.
• Spinzi G, Amato A, Imperiali G, Lenoci N, Mandelli G, Paggi S, Radaelli F, Terreni N, Terruzzi V. Constipation in the elderly: management strategies. Drugs Aging. 2009;26:469–474.
• Eastwood MA, Robertson JA, Brydon WG, MacDonald D. Measurement of water-holding properties of fibre and their faecal bulking ability in man. Br J Nutr. 1983;50:539–547.
• Lanza E, Yu B, Murphy G, et al. The Polyp Prevention Trial Continued Follow-up Study: No Effect of a Low-Fat, High-Fiber, High-Fruit, and -Vegetable Diet on Adenoma Recurrence Eight Years after Randomization. Cancer Epidemiology Biomarkers & Prevention. 2007;16(9):1745-1752. doi:10.1158/1055-9965.epi-07-0127
• Ho KS. Stopping or reducing dietary fiber intake reduces constipation and its associated symptoms. World Journal of Gastroenterology. 2012;18(33):4593. doi:10.3748/wjg.v18.i33.4593
• O’Hearn A. Can a carnivore diet provide all essential nutrients? Current Opinion in Endocrinology, Diabetes & Obesity. 2020;27(5):312-316. doi:10.1097/med.0000000000000576
• Jaouen K, Richards MP, Le Cabec A, et al. Exceptionally high δ15N values in collagen single amino acids confirm Neandertals as high-trophic level carnivores. Proceedings of the National Academy of Sciences. 2019;116(11):4928-4933. doi:10.1073/pnas.1814087116
• Gray CA, Bartol FF, Tarleton BJ, Wiley AA, Johnson GA, Bazer FW, Spencer TE. Developmental biology of uterine glands. Biol Reprod. 2001;65(5):1311–1323. 
• Cooke PS, Spencer TE, Bartol FF, Hayashi K. Uterine glands: development, function and experimental model systems. Mol Hum Reprod. 2013;19(9):547–558.
• Spencer TE, Kelleher AM, Bartol FF. Development and function of uterine glands in domestic animals. Annu Rev Anim Biosci. 2019;7(1):125–147.
• Settlage DS, Motoshima M, Treadway DR: Sperm transport from the cervical os to the fallopian tube in women. A time and quantitative study. Fertil Steril 1973; 24:655
• Coutiho EM, Maia HS: The contractile response of the human uterus, fallopian tubes, and ovary to prostaglandins in vivo. Fertil Steril 1971; 22:539
• Xu N, Kwon S, Abbott DH, Geller DH, Dumesic DA, Azziz R, Guo X, Goodarzi MO. Epigenetic mechanism underlying the development of polycystic ovary syndrome (PCOS)-like phenotypes in prenatally androgenized rhesus monkeys. PLoS One. 2011;6:e27286. doi: 10.1371/journal.pone.0027286.
• vechnikova I, Svechnikov K, Söder O. The influence of di-(2-ethylhexyl) phtalate on steroidogenesis by the ovarian granulosa cells of immature female rats. J Endocrinol. 2007;194:603–609. doi: 10.1677/JOE-07-0238.
• Rodríguez HA, Santambrosio N, Santamaría CG, Muñoz-de-Toro M, Luque EH. Neonatal exposute to bisphenol A reduces the pool of primordial follicles in the rat ovary. Reprod Toxicol. 2010;30:550–557.
• M. A. Hasan, A. Ali Zahid, R. U. R. Syed et al., “Viscoelastic behaviour of Bovine Myocardiam and valvular tissue: applications in Bio prosthetic heart valve with enhanced properties,” in Proceedings of the Qatar Foundation Annual Research Conference Proceedings, HBKU Press Qatar, Ar-Rayyan, Qatar, March 2018.
• J. Nam, S.-Y. Choi, S.-C. Sung et al., “Changes of the structural and biomechanical properties of the bovine pericardium after the removal of α-gal epitopes by decellularization and α-galactosidase treatment,” The Korean Journal of Thoracic and Cardiovascular Surgery, vol. 45, no. 6, pp. 380–389, 2012.
• Bagetti Filho, H. J., Pereira-Sampaio, M. A., Favorito, L. A., & Sampaio, F. J. (2008). Pig kidney: Anatomical relationships between the renal venous arrangement and the kidney collecting system. The Journal of Urology, 179, 1627– 1630.
• Carvalho, F. S., Bagetti Filho, H. J., Henry, R. W., & Pereira-Sampaio, M. A. (2009). The bovine kidney as an experimental model in urology: External gross anatomy. Cells, Tissues, Organs, 190, 53– 58.
• Erdogan, S., & Kilinc, M. (2011). The morphometric development and arterial vascularization of bovine fetal kidneys in the prenatal period. Annals of Anatomy, 193, 530– 538.
• Abdullah BM. Composition, chemical and microbiological properties of Jordanian ovine organ meats. International Journal of Food Science & Technology. 2008;43(4):746-751. doi:10.1111/j.1365-2621.2007.01516.x
• Silva, MS AJ, Dahm, MS OJ, Hellberg RS. Bovine Liver Supplement Labeling Practices and Compliance With U.S. Regulations. Journal of Dietary Supplements. Published online November 5, 2020:1-16. doi:10.1080/19390211.2020.1834048