Podcast Summary
Opening up about food intolerances can lead to important self-recognition: Sharing embarrassing experiences can help us take health concerns seriously and communicate effectively to improve our quality of life
Being open about food intolerances, even in embarrassing situations, can lead to important self-recognition and necessary lifestyle changes. Catherine shared her experience of accidentally pooping her pants in a public place due to her lactose intolerance, which led her to take the issue more seriously and communicate her needs more effectively. The incident also served as a reminder that everyone can relate to uncomfortable bodily experiences and that there's no need to be ashamed. It's essential to understand the potential consequences of not addressing our health concerns and to advocate for ourselves when necessary.
Understanding Lactose Intolerance: A Digestive Disorder: Lactose intolerance is a digestive condition where the body can't fully absorb lactose, leading to symptoms like bloating and abdominal pain. It's caused by a lack of the enzyme lactase, which breaks down lactose in the small intestine.
Lactose intolerance, also known as lactose malabsorption or hypolactasia, is a common gut problem where the body has difficulty digesting lactose, a sugar found in milk and dairy products. The symptoms, which include bloating, abdominal pain, and passing gas, are caused by an inability to fully absorb lactose in the small intestine. To understand this condition, it's important to first know how the gastrointestinal tract functions normally. The gut has three main divisions: the foregut (mouth and stomach), midgut (small intestine), and hindgut (colon and rectum). Digestion begins in the mouth, where food is chewed and physically and chemically broken down. It then moves to the stomach, where the digestive process continues through physical churning and the presence of stomach acid. As food enters the small intestine, its main goals are to finish digestion and absorb nutrients. The small intestine contains enzymes that break down nutrients into small molecules, allowing them to pass through the intestine wall and enter the bloodstream. Lactose intolerant individuals lack the enzyme lactase, which is responsible for breaking down lactose, leading to the symptoms associated with lactose intolerance.
Understanding Lactose Intolerance: The Role of Lactase in Digesting Dairy: Lactose intolerance occurs when the body can't produce enough lactase to break down lactose in milk, leading to digestive discomfort from gas and diarrhea.
Our digestive system, specifically the GI tract, works to break down food into nutrients that can be absorbed in the small intestine. However, when we consume complex sugars, like lactose, which is a disaccharide found in milk and dairy products, our bodies need the specific enzyme lactase to break it down into simpler sugars, galactose and glucose. If lactase production is insufficient or absent, undigested lactose reaches the colon, where bacteria feed on it and produce gas and diarrhea as a result. This condition is known as lactose intolerance or lactose malabsorption. It's not a disease, but rather a common digestive issue affecting many people, particularly those of non-European descent. Understanding this process helps explain why consuming dairy can lead to uncomfortable symptoms for some individuals.
Lactose intolerance vs Lactase nonpersistence: Lactose intolerance and lactase nonpersistence are distinct conditions. Lactose intolerance is having symptoms after consuming milk due to a lack of lactase enzyme, while lactase nonpersistence is the inability to produce lactase in adulthood. Some lactose intolerant individuals can still tolerate small amounts of milk.
Lactose intolerance and lactase nonpersistence are not the same thing. While lactose intolerance refers to having symptoms after consuming milk due to lack of lactase enzyme, lactase nonpersistence is the inability to produce lactase in adulthood. However, even lactose intolerant individuals can tolerate some amount of milk, around a cup a day. In Northern European countries, where lactase persistence is common, people may consume lactose-free or low-lactose products due to misunderstanding their own tolerance levels. Lactose malabsorption can also result from premature birth, GI tract infections, or developmental issues. But the most common cause is the normal downregulation of lactase enzyme production as we age. Therefore, if you can drink milk as an adult without symptoms, you are likely a lactose persister, a mutant state in the human population. Finns and other Northern Europeans, with their high prevalence of lactase persistence, may have a better understanding of their tolerance levels and consume more lactose-containing products as a result.
Lactose Digestion and Cultural Significance of Milk: Some people naturally produce enough lactase to digest milk, while others don't. Probiotics may help, but there's no substitute for the body's natural ability to produce lactase. Milk holds cultural significance and has been attributed to divine origins.
The ability to digest lactose, a sugar found in milk, varies greatly among individuals. Some people produce enough lactase, an enzyme needed to break down lactose, throughout their lives, while others do not. The gut microbiome and certain bacteria play a role in lactose digestion, and studies suggest that probiotics may help increase tolerance. However, there is no pill or probiotic that can fully replace the body's natural ability to produce lactase. Milk has held significant cultural and mythological importance throughout history, with various civilizations attributing its origins to milk from gods or mythical creatures. The belief that milk was a type of blood persisted for a long time, and it was even used as the blood of Christ in the Catholic church before being replaced by wine. The distinction between cow milk and human breast milk can be confusing, but it is essential to understand that lactase persistence refers to the specific genetic trait that allows individuals to digest lactose throughout their lives.
Milk: A Significant Source of Nutrition and Cultural Importance Throughout History: Milk, from human breast milk to animal milk, has been used as food, sacrifice, and even poison throughout history. Humans are unique in consuming milk from other species throughout their lives, making it crucial for survival during food scarcity. Milk has played a fascinating role in human history, from the first refrigerator to attempts to poison leaders.
Milk has held significant cultural, nutritional, and historical importance for humans and various animal species throughout history. From human breast milk to animal milk like cow, goat, and sheep milk, milk has been used as food, sacrifice, and even poison. Milk was once considered a low-status beverage due to its perishability, leading to cultural tensions and conflicts. Not all mammal milk is created equal, with some being much fatter than others. Humans are the only mammals that consume milk from other species throughout their lives, making it crucial for survival during food scarcity. Milk has been a source of nourishment and conflict for centuries, with lactose intolerance being a recognized issue for a significant portion of the population. From the first refrigerator built to keep butter in 1803 to the CIA's attempt to poison Castro with poisoned ice cream, milk has played a fascinating role in human history.
Lactase persistence and pastoralism: Lactase persistence, the ability to digest milk as an adult, is common in populations with a history of pastoralism or dairy farming. The mutation that allows for lactase persistence likely emerged around 8000-9000 years ago in Central Europe, providing advantages in pastoralist societies by offering additional nutrition.
The prevalence of lactase persistence, the ability to digest milk as an adult, varies greatly across different populations around the world. This trait is most common in populations with a history of pastoralism or dairy farming, such as in Europe, Scandinavia, Northern India, and some pastoralist groups in Africa. The hypothesis is that lactase persistence emerged and was selected for after the adoption of pastoralism, making it beneficial for survival and reproduction. Milking animals, particularly goats, sheep, and camels, likely began much earlier than previously thought, around 11000-10000 years ago. The mutation that allowed humans to continue producing lactase into adulthood likely emerged around 8000-9000 years ago in Central Europe. This mutation provided advantages in pastoralist societies by providing additional nutrition and contributing to the widespread prevalence of lactase persistence in certain populations.
The evolution of lactase persistence in Northern Europe may be linked to dairy farming and cultural traditions: Lactase persistence, the ability to digest lactose into adulthood, may have evolved in Northern Europe due to cultural practices like dairy farming and consumption of fresh milk, providing benefits such as access to vitamin D and improved calcium absorption.
The ability to digest lactose into adulthood, which is associated with lactase persistence, may have evolved due to the cultural tradition of keeping livestock and consuming fresh milk, particularly in Northern Europe. This hypothesis is supported by the fact that lactase persistence is more common in Northern European populations compared to those in the Mediterranean, where cheese is the main dairy product consumed. The evolution of lactase persistence may have provided selective advantages, such as access to vitamin D during winter months and improved calcium absorption. Additionally, milk may have served as a source of water in arid environments, making lactose tolerance crucial for survival. The Proto Indo Europeans, an ancient group whose existence is mostly inferred from linguistics, are believed to have spread across Europe, Western Asia, and the Indian subcontinent around 5-6000 years ago, and their culture and language, which included the widespread use of dairy farming, influenced the languages spoken by half of the world's population today.
Lactose intolerance and milk consumption: Recent research shows lactose intolerant individuals can consume up to 12 grams of lactose without symptoms, debunking the belief that milk should be avoided. Distinguishing lactose intolerance from milk allergies and managing symptoms is crucial for improving quality of life.
Despite lactose being discovered relatively recently and lactose intolerance only getting a formal definition in the 20th century, milk consumption continues to be high, especially in countries where lactase persistence is low. This has led to a significant amount of bias in medical advice, as milk was often recommended for various health reasons without considering the effects on those who can't digest lactose. However, recent research shows that even lactose intolerant individuals can consume up to 12 grams of lactose in a single sitting without becoming symptomatic. This is equivalent to a whole glass of milk or a large amount of cheese. It's important to note that lactose intolerance is different from milk allergies, which are caused by an allergic reaction to the protein casein found in milk. Additionally, the symptoms of lactose intolerance can overlap with symptoms of other conditions like IBS, making it difficult to determine the root cause of symptoms. Therefore, there is a growing interest in treating or managing lactose malabsorption to improve overall quality of life.
Milk is not the only source of calcium: Calcium can be obtained from various sources including seafood, legumes, leafy greens, lactose-free dairy, and fortified non-dairy milks
While milk has long been considered an essential part of the diet for calcium intake in the United States, especially for those living in northern latitudes due to the addition of vitamin D, the rise of lactose-free products and non-dairy milk options means that those who are lactose intolerant or choose to avoid dairy have alternative ways to obtain calcium. Historically, people obtained calcium from various sources such as seafood, legumes, and leafy greens. While calcium deficiency is a risk for osteoporosis, studies have shown that in places where people don't consume dairy, osteoporosis is not more common. Additionally, there are lactose-free dairy options such as cheese and certain types of yogurt, as well as fortified non-dairy milks. So, while milk may be a significant source of calcium in the US diet, it is not the only option.
The Evolution of Lactose Tolerance in Humans: A genetic mutation enabled some populations to produce lactase in adulthood, allowing them to digest milk and derive nutritional benefits, shaping their own evolution through interaction with their environment.
The ability of humans to digest lactose, a sugar found in milk, is not a natural trait for most adults. This condition, known as lactose intolerance, is the result of a genetic mutation that became prevalent in certain populations due to a process called niche construction. This was discussed in the article "2009 and the Evolution of Lactase Persistence" by Gurbal et al. (2011), which we will link on our website, thispodcastwillkillyou.com. Lactose intolerance is a clinical syndrome that affects the digestive system when lactose is not properly broken down, leading to symptoms such as bloating, diarrhea, and flatulence. However, in some populations, such as those of Northern European descent, a mutation allowed for the production of lactase in adulthood, enabling them to digest milk and derive nutritional benefits from it. This mutation became prevalent due to a combination of factors, including the availability of dairy products and the selective pressures of the environment. This is an example of how humans have shaped their own evolution through their interaction with their environment. We were joined in this episode by Katie, who shared her personal experience with lactose intolerance, and we also want to thank Bloodmobile for providing the music for this episode. As always, thank you to our listeners for tuning in.
