Got milk? You shouldn't have

It was requested, so I have decided to write about THE topic which really inspired me to become passionate about the direct link between food and disease. I've always been interested in nutrition in general, but during grad school I took a vegetarian nutrition course which changed my life and I hope that by passing on some of this information you, too, can make some lifestyle changes for better long term health.

The topic: milk.  When I first starting learning about the less than desirable qualities of milk (and all dairy products made from milk) I was a bit skeptical. We have all been told ever since we can remember that milk is good for us. I specifically remember, as a child, being made to sit at the dinner table until I finished my glass of milk. Where will you get calcium? We all need milk to grow up big and strong right? WRONG. As I have read about and seen and heard first hand, this is a controversial subject. Many of you may be skeptical I like first was, but try to keep an open mind and if you're so inclined, do some research yourself.  There is an abundance of evidence that strongly suggests that dairy, may in fact, be one of the worst components of the American diet.

Before I get deeper into this I need to put out a disclaimer: I am a hypocrite - I do eat dairy.  Not everyday and not in large quantities, but I do enjoy a slice of pizza every now and then or a bowl (pretty large) of ice cream.  For awhile I was good at avoiding all dairy but it's hard!  However, I am going to try again, starting today!

The first thought I'd like you to ponder is this: Humans (Western societies in particular) are the only species on this planet that consumes milk beyond infancy.  Moreover, we chose to consume cow milk, which is a complex, bioactive substance produced with a nutrient profile for the growth and development of a baby bovine, who will gain, on average, 1.5-2.0 pounds per day and should reach over 500 pounds when full grown.  Do we really need the same nutrition designed for a heifer?  Would it not be more suitable and 'natural' to consume ape milk, the species we consider most close to us on a molecular level?

While not very publically revealed or even publically accessible, much research has been conducted on the role of milk in various diseases. Below is a very brief synopsis of the findings that I know about (keep in mind that there is much more research out there that I hope to read):

~ Through multiple research studies, the main protein in milk, casein, has shown to be a potent instigator of cancer initiation (sets the stage) and promotion (increases tumor growth).  What's more is that the level of protein in the diet has been shown to directly correlate with tumor growth.  Dr. Thomas C Campbell, former head of the biochemistry department at Cornell University, has shown through various studies that the level of casein consumption can literally control the growth of cancer cells.  Provide protein (in the form of casein) to cells exposed to a carcinogen, at 20% of daily calorie needs, and 100% of subjects (mice) develop cancer.  However, provide the protein at 5% of daily calorie needs and ZERO subjects develop cancer (with the same carcinogen exposure).   A ratio of 100:0 is RARELY seen in science.  Further, when Dr. Campbell lowered the protein level in the mice who had cancer, from 20% to 5% of daily calorie needs, the tumors stopped growing!  When given back the 20% protein, the tumors began to grow again.  Tumor growth was turned on and off, like a light switch, by one change - the amount of protein in the diet.  But, what about plant protein? When these experiments were repeated, with wheat protein (gluten) and soy protein, tumors showed no growth at any level of protein in the diet.  One argument that has been thrown at this research is that many things are possible carcinogens, when given in high enough quantities (you may be familiar with the artificial sweetener debate).  But, in this research, protein was provided at levels NORMALLY consumed by humans.  The average U.S. adult consumes ~16% of calories from protein, and many individuals consume a lot more than that! This isn't laboratory data that is isolated from the real world. Rather it mirrors the real world!

Molecular studies conducted on how casein affects cancer revealed multiple different mechanisms by which this dietary component wreaks havoc on cells.  When the protein is provided at higher levels:
1. More carcinogens enter cells
2. Cells multiply faster
3. Enzymes that naturally detoxify carcinogens showed reduced activity
4. More carcinogen-DNA damage sites were formed (damaging DNA = potential cancer initiation)

Dr. Campbell went on to conduct one of the most comprehensive human nutrition studies and found that his lab findings of protein consumption and cancer were highly consistent with human protein consumption and cancer.  That is - humans who eat more animal based products have higher rates of almost all types of chronic disease. Some have tried to argue that it is the fat in these products that is the culprit. However, there is much evidence that just cutting out animal fat (drinking skim milk, eating low fat white meat) does not lead to lower cancer rates.  I wish I could put the graphs in this post but I can't figure out how, but data from countries around the globe provides convincing evidence that total fat intake does not necessarily correlate with cancer incidence.  What the evidence does indicate is that there is a direct, strong correlation between animal fat intake and cancer (breast specifically), but no correlation at all between plant fat (even saturated fat) and cancer.  Could it not be the fat in the animal products, but the protein instead?  If fat is the bad guy, then taking fat out of the diet should decrease cancer rates. However, Americans are eating more 'low-fat' and 'reduced-fat' products now, in this age of processed foods, and even though the death rate of many cancers has leveled off or even declined (likely due to better detection and treatment methods), the incidence of most cancers has not.

~ Like I mentioned in a previous post (McAcne), milk is full of hormones which are intended to aid in the growth of a baby cow.  Regarding human consumption, one of the most important hormones to consider is insulin and its family of insulin-like growth factors (IGF).  These hormones are necessary for proper growth, development and homeostasis of multiple organ systems.  Due to their roles in growth and development, IGFs are potent stimulators of cell proliferation and inhibitors of cell apoptosis (programmed cell death).  Hormones are signaling molecules that cross cell membranes and deliver their message to a cell's nucleus, the house of DNA. Milk contains active IGF-1 and IGF-2.  When you drink milk you are ingesting hormones that can directly interact with your cells' epitome, altering genetic activity.  These disturbances in DNA activity have wide and long-ranging results.  From in the womb up until old age, the excess IGFs ingested from dairy products exert negative effects on human health.  Just a few ways too much IGFs and their signaling system contribute to less than optimal health are shown in the two figures below.

As you can see you can greatly reduce your risk of multiple chronic diseases by taking dairy out of your diet. What about calcium you ask? Well that will be another post at some point but just know for now that you can still get enough calcium from plant products. Soy milk and almond milk are great substitutes. Calcium is actually found at some level in almost all whole, plant foods.  Some good sources are nuts (especially almonds), beans, leafy greens and broccoli (see table below). If you're a tofu fan, it, too, is a good source of calcium.  Moreover, individuals who do not consume animal products likely need LESS calcium than those do chose to eat meats and dairy. This is because animal proteins alter the pH of the blood, making it more acidic, and the body's best buffer to neutralize the extra acid -- calcium! Calcium is pulled from bones to be used in the blood as a buffer and then is subsequently excreted in the urine.  Those who eat animal products loose more calcium in urine and therefore need to take in more calcium from food.  But, the details about all this can be saved for another post about bone health.

If you want to do more reading yourself about this controversial subject I will point you to two sources:

The China Study by T Colin Campbell (lots of science but written for the general public)

Melnik BC. Milk - The promoter of chronic Western diseases. Med Hypotheses (2009) doi: 10.1016./jmehy.2009.01.008  (lots of scientific explanations)

Polyphenols = polyprevention

The Nerdy Science
I, along with many of my friends, will tell you that I am a nerd.  I get excited over really weird things.  A lot of the things I get excited about revolve around science.  The latest thing I've been intrigued by are polyphenols.  Polyphenols are a class of phytochemicals (plant chemical) characterized by multiple benzenoid rings attached to hyroxyl (OH) groups (see picture on right, green tea phenol). These compounds are only found in plants and are intended to help protect plants from photosynthetic (sun) damage and protect against reactive oxygen species (hyperactive particles that damage DNA). 

Here is where epigenetics comes in!  (This may get a bit technical for some, I apologize).  DNA can be modified via three different mechanisms: methylation (attachment of a methyl group, -CH3), histone modification (histones are proteins that DNA is wrapped around), and post-transcriptional gene modification by microRNAs. These processes affect gene product stability, DNA folding and complete nuclear organization of gene material.  Although polyphenols affect each of these processes I want to focus on  DNA methylation.  When specific segments of DNA have too many methyl groups attached, the gene product of that DNA is 'silenced.' Conversely, when these regions have very few methyl groups attached they are active and produce gene products. It is now believed that hypermethylation (silencing) of tumor suppressor genes is one of the leading causes of tumor initiation and progression.  In other words, it's a lack of signal from silenced DNA that tends to lead to cancer - not a new signal from active DNA.  Think of the methyl groups as dumbbells - the more that are attached to the DNA, the more the DNA is weighed down and not able to replicate normally.

How do polyphenols fit in to all of this? Polyphenols actually directly inhibit the enzyme that attaches methyl groups to DNA. Therefore, they block gene silencing by keeping the DNA free from the dumbbells! They allow active tumor suppressor gens to keep being made (more tumor suppressor gene activity = more natural cancer defense).

The Lesson for Everyday Life
Polyphenols are essential for human health.  With your new knowledge of the science behind polyphenols I'm sure you won't be surprised to learn that there is much evidence that suggests that populations with high pholyphenol intake have lower rates of all types of cancer.  Now there are over 8,000 dietary polyphenols! Remember polyphenols are only found in plants (spices included).  Listed below are just a few that have been found to help keep DNA free of methyl groups.

 Various polyphenols from these and additional fruits, vegetables and spices have been found to inhibit the growth of MANY types of cancer cells in vitro (in lab conditions) including: breast, colon, prostate, cervical, lung, esophageal, skin, uterine, leukemia and lymphoma.

Keep in mind that drinks made from plants count too. Tea, coffee, soy milk and wine are actually great sources of polyphenols!


So, what little steps can you do add these protective compounds into your diet:

1. Add spices to foods.  Instead of going for the salt shaker, try novel spices on your veggies. Sprinkle garlic powder, paprika, curry powder, dill or cumin on steamed veggies.  One of my favorite things to do is to add a dash of cinnamon to my morning coffee. It gives it a different flavor and I'm getting the benefits of cinnamon (cinnamon also helps stabilize blood sugars). 

2. Try to get the recommended number of servings of fruits and vegetables (newer recommendations are up to 9 servings!). Divide your plate in half, whether it be breakfast, lunch or dinner, and make sure that 1/2 of the plate is made up of fruits and/or vegetables. These foods also help keep you full longer because of their higher fiber content and increased water content compared to meats and carbohydrates. Now don't be overwhelmed by the number of servings. Serving size is what matters. One commercially harvested apple bought at a regular grocery store is large enough to be 2 servings. Only 1 cup of spinach or lettuce, a palmful, is a serving.  You only need to have 4-5 spears of steamed broccoli to count as a serving.  You really can get at least 5 servings/day by just eating a large piece of fruit and a medium-sized salad. Challenge yourself to try a new vegetable or fruit you have never had before at least once a month!

3. Choose green tea (unsweetened preferably) or coffee as your morning beverage.

4. Try soy!  Edemame (soy beans that look like snap peas in their pod) and soy milk are great substitutes for meat and cow milk, respectively. I love vanilla soy milk in coffee and cereal!


Keep in mind that many other things in your environment can affect DNA function and that the research on how food compounds directly affect DNA is still in it's infancy.  However, like I mentioned earlier we do know that populations that consume the highest amounts of fruits, vegetables (and other nutrient dense foods like whole grains and legumes) do have some of the lowest cancer rates.  While there is still much to learn, there is little risk in incorporating polyphenol rich foods into your everyday diet!