Milk is an area where humans are far removed from their food source, and milk is so second nature that we do not even think about the origin of the food. If we saw a cow in a field, would we even think to walk up and suck its teat for our nutrition? Possibly, if we were starving, but I cannot imagine another scenario.
Over three-quarters of the world’s population does not drink milk, according to the Food and Agriculture Organization of the United Nations (FAOSTAT 2013). The reason for not drinking milk might be for multiple causes, including cultural, economic, and biological.
Most of the world’s population are lactose intolerant and become physically ill if they consume animal milk or milk products.
Lactose intolerance is the inability to digest the milk sugar lactose, causing gastrointestinal symptoms of flatulence, bloating, cramps, and diarrhea in some individuals. When children are born, they produce a lactase enzyme that will break down lactose into its simpler forms, glucose and galactose sugar, in their mother’s milk. Lactase enzyme levels normally change over a person’s lifespan. They rise rapidly in the first week after birth and start to fall from about three to five years of age. This time frame is also when the average human stops nursing and weans their young, as well as the time that the brain stops growing and has reached the cranial capacity. According to Kathy Dettwyler, the natural age of weaning analogous to other primates is a range from two and a half years to seven years. Lactase enzymes then fall sharply in later childhood.
Although it is named “lactose intolerance,” a shortage of the lactase enzyme is really the normal state of adult humans in the world. The lowest rates of milk consumption are in Africa and Asia, and these two regions have also shown to be the most milk intolerant with the least amount of lactase enzymes to digest milk. Approximately 70 percent of African Americans, 90 percent of Asian Americans, 53 percent of Mexican Americans, and 74 percent of Native Americans are lactose intolerant. The true minority are the people who are generally of European descent who have the genetic mutation that has allowed the lactase enzyme to be persistent into adulthood.
No animal in the entire world drinks milk past the age of weaning except humans.
The carbohydrate, protein, and fat content of milk from each species is finely tuned to meet the nutritional requirements of that particular animal. The protein content in cow’s milk is more than triple that of human milk; this is because the amount of protein in milk is linked to the amount of time it takes each species of animal to grow in size. According to the Centers for Disease Control and Prevention, cow’s milk is unfit for a human child to consume when that child is under the age of twelve months. Human breast milk is one of the lowest protein milks in the mammalian world. Compositionally, breast milk is on average less than 8.5 percent protein/amino acids, and breast milk fulfills 100 percent of the dietary need of a child during the stage of brain development. In comparison, a cow has 33.6 percent protein/amino acids.
The cow’s milk that adult humans drink is made for a calf that is born with a birth weight of 80 pounds. The calf is expected to gain over 1,300 pounds in one year and grow to its adult weight of 1,400 pounds by drinking its mother’s milk. You can therefore see that the nutritional requirements for that milk will be different than those for a human.
The proteins in milk can be divided into two categories: caseins and whey proteins. Human milk contains these in a ratio of 40:60, respectively; while in cow’s milk the ratio of casein to whey proteins is 80:20. Furthermore, cow’s milk contains a significant amount of fat, which is why milk packaged for human consumption is available in a number of different fat contents, labeled whole milk, 2 percent milk, ½ percent milk, or skim milk. The percentage with which each type of milk is labeled is the percentage of the weight of each type of milk that is made up by milk fat.
Based on the differences between animal milk and human milk and the differences in nutritional requirements in humans and the animals whose milk we consume, Dr. Walter Willett, chair of the Department of Nutrition at the Harvard School of Public Health, states,
“Humans have no nutritional requirement for animal milk...”
And What about Calcium?
Calcium is the element that makes up 99 percent of our bones and is the fifth most abundant element in our bodies. We have a strange belief that calcium only comes from milk or milk products, such as cheese or ice cream, and that we are in constant need of replenishing our calcium from milk. The recommended daily intake of calcium in the United States is 1,000 mg, but it is worth noting that the recommended daily intake in Europe for adults is 700 mg, and in parts of Latin America the recommendation is not daily, but twice weekly. These differences indicate that nutrition science is still evolving to determine the amount of calcium that humans need.
According to the National Osteoporosis Foundation (NOF), osteoporosis, or “porous bones,” is a disease that occurs when the body is losing too much bone, meaning that the calcium is leeching from the bones and being excreted in the urine. About 54 million Americans have low bone mass, placing them at increased risk for osteoporosis. Studies suggest that approximately one in two women and up to one in four men age fifty and older will break a bone due to osteoporosis. Many factors contribute to bone loss, including use of certain prescription medications, additional diseases, and nutrition. Drugs such as steroids, chemotherapy drugs, and heparin, as well as many others, have been shown to increase bone loss. Diseases ranging from breast cancer to celiac disease to Parkinson’s and many others have also been linked to bone loss.
Ten million Americans have osteoporosis.
Nutritional factors also affect bone loss. Calcium requirements vary from person to person depending on such factors as intake of vitamin D (primarily through exposure to the sun), intake of animal-source proteins, and intake of sodium potassium salts, and physical activity. Vitamin D and potassium chloride are essential for calcium absorption and the avoidance of calcium excretion.
If someone tells you that you need to take a calcium supplement, make sure that you have been tested for vitamin D and potassium. Calcium does not absorb into your body if you are not maintaining an adequate level of vitamin D and potassium chloride.
In regards to animal-source protein and sodium, your body is constantly balancing your pH, or the amount of acid and alkalinity in your body. (pH is discussed more in depth in Chapter 3: “Salt, Sugar, pH, and Water.”) When you eat a lot of acidic food and you have a stomachache, you reach for a Tums or Rolaids, which is essentially calcium. Calcium is a neutralizer or buffer for acids entering the body. When you continuously eat a lot of acidic food, such as animal products and foods that are high in sodium, the acid needs to be neutralized. Calcium will neutralize the acid formed from the consumption of animal products. The calcium in your bones is an internal neutralizer, and your body will excrete it if your acidity level is too high.
Those of European descent take in more calcium by far than any other group in the world. They also eat the most acidic foods and animal products in the world, and have the highest rate of bone and joint disease in the world, especially arthritis and osteoporosis. The Asian, African, Mideast, and Latin cultures take in the least amount of calcium. They also generally have less arthritis, osteoporosis, and other such conditions. Hip fracture rates are more common in developed countries, where the calcium intake is higher, and less common in developing countries, where calcium intake is lower. This is generally referred to as the “calcium paradox,” and this paradox points to the continuing need for nutrition science to evolve.
One of the primary components of milk is a growth factor called Insulin-like Growth Factor (IGF-1). The amount of IGF-1 present is higher in milk produced by pregnant cows. This growth hormone is present in both organic and nonorganic cows. It is not injected; it is natural to the cow. The concern is that because IGF-1 in cows is identical to human IGF-1, humans are overconsuming IGF-1 through their consumption of milk products and therefore increasing the rate of cell growth in humans.
Cancer is made up of cells that grow out of control, and, perhaps not surprisingly, IGF-1 has been linked to an increased risk of childhood cancers, breast cancer, lung cancer, gastrointestinal cancers, melanoma, and cancers of the pancreas and prostate (LeRoith et al., 1995; Chan et al., 1998; Epstein, 1996).
According to Harvard, diets that are very high in calcium may increase the risk of prostate cancer. High calcium intake is also associated with kidney stones.
A recent review of thirteen combined studies that looked at high levels of calcium in relationship to cardiovascular disease from I. R. Reid, published in the Journal of Internal Medicine, suppo rts that a high level of calcium is associated with a higher risk of vascular disease and death. In this article, over thirteen studies are reviewed that support the fact that cardiovascular disease or heart attacks and str
okes are linked to higher calcium levels. You should be able to receive all the calcium you need from your daily nutrition through plant based sources. The following table shows plant that are high in calcium.