Read It Starts With Food: Discover the Whole30 and Change Your Life in Unexpected Ways Online
Authors: Melissa Hartwig,Dallas Hartwig
It Starts With Food: Discover the Whole30 and Change Your Life in Unexpected Ways (18 page)
The discussion of dairy
*
is one that interests many people and has no simple, black-and-white answers. There are many functional components of dairy that, depending on the source and the individual consuming it, can be highly problematic, generally benign, or even beneficial.
The real challenge is twofold: being honest with yourself about whether dairy is “just fine” or just the opposite, and actually finding a truly high-quality source of dairy if you are one of the people who benefit from it. Luckily, the Whole30 will help you with the first part of that challenge. In the meantime, let’s talk about some of the science about dairy consumption.
Cow’s milk is the perfect food ... if you are a calf. Likewise, human breast milk is the optimal food when you are an infant.
Milk is an excellent source of energy and building blocks to rapidly grow mammals that are too young to eat adult food, such as grass (cows) and a wide range of plants and animals (humans). Until a mammal’s digestive system (including teeth) has completely developed and it can eat whole food, mother’s milk supplies optimal nutrition.
But mother’s milk is not just an inert supply of carbohydrate, protein, and fat—though it contains significant amounts of all of those macronutrients. And yes, milk also contains calcium—but what is critical to understand is that milk is so much
more
than calories and calcium!
Milk is a blend of bioactive substances that not only promote aggressive growth of a very young mammal (doubling or tripling bodyweight in a very short period of time), but also ensure the complete development of the young one’s immune system. You are born with the basic framework of an immune system, but there are some missing elements which must be “supplemented” by consuming mother’s milk. In this context, milk is the perfect food, and the perfect messenger.
These growth, hormonal, and immunity messages from mother’s milk to newborn are biologically healthy and appropriate,
when you are a calf or an infant
. However, once weaned, calves and human infants no longer grow at such an aggressive rate, and their digestive systems and immune systems are complete. This means the growth and immunological messages from mother’s milk are no longer needed, nor appropriate.
And when the biological messages
intended for a calf
are being received loud and clear by
your adult human body
, they are even
less
appropriate—and potentially downright harmful.
To demonstrate how dairy products generally fail at least one of our Good Food standards, let’s talk about the already well known components of dairy (protein, carbohydrate, fat, and calcium), as well as some of the other lesser-known components.
Though there are dozens of dairy proteins, they can be divided into two categories—
casein
and
whey
. Casein makes up about 80 percent of total milk protein and acts as a source of amino acid building blocks that the calf can digest and turn into muscle, connective tissue, skin, hair, hormones, and enzymes and even form part of the structural matrix of bones and teeth. Calves are able to make good use of that species-specific protein supply to fuel their aggressive growth.
While children are still growing, they are no longer developing at the same aggressive rate as they did as infants. (Even teenage boys are not tripling their body weight in months!) Once they are weaned from breast milk, it simply doesn’t make sense to keep sending children the growth, hormonal, and immune messages they needed when first born—and it’s certainly inappropriate to send them biological messages intended for
newborns of a different species.
Growing kids do need adequate energy (calories!), protein, healthy fats, and micronutrients, but their age- and species-appropriate food is nutrient-dense omnivorous fare: meat, seafood, eggs, vegetables, fruit, and healthy fat sources like coconut, olives, and avocado. The bottom line: Once your toddler is weaned and eating real food, there is
no need
to supplement his or her healthy diet with cow’s milk. (Not to mention that dairy consumption has been linked to a variety of medical conditions in children, including acne, asthma, juvenile myopia, insulin resistance, and type 1 diabetes.)
There are also compounds in milk that have a specific
physiological
function—proteins and “peptides” (short amino acid chains)—in the body of the intended recipient (offspring). For instance, protein sequences embedded in casein’s molecular structure are released during the digestion process and send a message from mother to young.
Casein exorphins, or
casomorphins
(morphine-like substances derived from casein), are one category of these milk-derived protein fragments. Casomorphins are able to cross the gut barrier in young mammals (and in adults with increased gut permeability) and bind to opioid receptors in the enteric and central nervous systems. Casomorphins have been shown to slow down the movement of food through the gut (thanks to their morphine-like effects).
Again, let’s underscore the biological context here: the presence of casomorphins in human breast milk or cow’s milk is unlikely to be harmful to infants or calves (respectively), and probably serves to strengthen the bond between mother and young, improving feeding behavior and therefore improving the odds of survival of the newborn mammal. But the effects of these potently bioactive “food hormones”
from another species
on human adults remain largely unknown
.
*
Cheese is most commonly made from concentrated casein that has been blended with enzymes that partly digest the casein molecules, liberating some of these morphine-like compounds. Is it any coincidence that a large majority of our clients and seminar attendees say that cheese is the dairy product that would be the hardest to give up? No one knows for sure whether this represents a violation of our first Good Food standard (healthy psychological response)—but we sure do find it fascinating.
Casein, especially when it comes from aged cheese, also causes a specific type of immune system reaction called a
histamine response
in many people. (So for susceptible individuals, dairy would fail our fourth Good Food standard as well.) Histamine intolerance can cause headaches, GI upset, exacerbations of asthma, and seasonal allergies.
It is unclear what percentage of the population has this response, but until you have completely removed all dairy proteins from your diet for a period of time, you won’t know whether or not you are affected.
Casein shares some structural similarities with components of gluten. This means that gluten-sensitive individuals (including those with celiac disease) are less likely to tolerate casein-containing dairy products. Research suggests that about 50 percent of celiacs are also sensitive to milk. In genetically susceptible individuals, the incomplete breakdown of peptides with opioid activity like those from gluten or casein (in the presence of intestinal permeability) allows these fragments to enter the circulation and potentially influence neurological functioning, resulting in or exacerbating disorders such as postpartum psychosis, schizophrenia, and autism.
The other major category of milk protein is
whey
. Whey is a blend of multiple types of smaller proteins and hormones, including immunoglobulins, insulin, insulin-like growth factor 1 (IGF-1), estrogens, and other growth factors. (Remember, milk is a powerful growth promoter!) For this reason, milk is a highly
insulinogenic
food, which means that the combination of lactose plus whey dairy proteins causes the release of very large amounts of insulin when consumed.
This makes perfect sense: it all starts with biology.
The “building-storing” function of insulin is in
complete accordance
with the aggressive growth going on in those breast-feeding months. Lots of growth means lots of insulin is needed to aggressively store nutrients. But the remarkably large amount of insulin secreted in response to milk and whey protein intake is largely why dairy may fail our second Good Food standard for those with metabolic syndrome; in this population, it does not promote a healthy hormonal response.
Marketing from some supplement companies will suggest that a large insulin response (especially after exercise) will help drive nutrients into cells to maximize recovery, but you don’t need an insulin “spike” after exercise to jam nutrients into cells, because your body is more insulin sensitive immediately post-workout. In this state, nutrient uptake is elevated—meaning you can “sneak” nutrients into cells
without
large amounts of insulin. In addition, the frequent insulin spikes from regular consumption of whey protein could be harmful in a manner similar to chronic overcarbsumption and the resulting hyperinsulinism in those with metabolic syndrome. We don’t believe whey protein supplements are a good choice for the majority of people (especially those who are insulin resistant and overweight), although they
may
be an easy protein source in specific circumstances for lean, insulin-sensitive, performance-driven athletes. (Casein protein supplements, while not highly insulinogenic, are poorly tolerated, and we never recommend them.) In general, opt for nutrient-dense meat, seafood, and eggs instead of nutrient-poor processed dairy proteins after exercise.
Anyone seeking to improve insulin sensitivity (or avoid becoming insulin resistant) would be best served by avoiding dairy products, including those that contain highly insulinogenic components, like sugar-sweetened yogurt or kefir, milk (regardless of fat content), whey protein powder, and, of course, ice cream. (Do we really have to tell you that ice cream is not healthy? And p.s., it’s not the dairy fat that’s the problem.)
Insulin is not the only potentially detrimental hormone increased by milk. Milk consumption also significantly elevates IGF-1, another powerful growth-inducer. IGF-1 promotes growth in children, but it is also associated with promotion (or indirect facilitation) of various cancers, such as breast, colon, and prostate. Of course, we’re not saying that if you drink milk, you’ll get cancer, but if you’re at high risk, consuming substances that increase the growth of cells, including abnormal cells, seems unwise.
But there is more to this story than just the protein fractions of milk—the carbohydrate component can also pose problems. The kind of carbohydrate found in milk is called
lactose
. While there are not huge amounts present in milk (and some other dairy products have very little because of processing), lactose is an issue for a surprisingly large percentage of people. Most infants digest lactose well, but after weaning, most of us lose the ability to convert lactose into usable forms of carbohydrate (glucose and galactose).
If lactose cannot be properly digested, bloating and gastrointestinal upset may result. In addition, consuming even small amounts of lactose may contribute to an imbalance of gut bacteria, promoting dysbiosis. For those who can no longer effectively digest lactose (i.e., most of us), dairy would also fail our third Good Food standard (promotes a healthy gut).
However, lactose intolerance is not our biggest concern with dairy, given its propensity to stimulate insulin production and potential to trigger an immune system response. In fact, many people who consider themselves lactose-intolerant (by observing that dairy makes them feel poorly) may have a sensitivity to dairy
proteins
as well.
Considering the various concerns raised by the scientific evidence, we think that a cautious strategy of eliminating milk (and dairy proteins) from your diet is both intelligent and healthy. Just as with grains, when you can get all the benefits of a food from other, healthier sources, why wouldn’t you?
Anytime we mention the whole “we don’t do dairy” thing, we inevitably get The Question:
The Question is generally coming from the perspective that strong, healthy bones are important and that calcium builds strong, healthy bones. We do not disagree. But despite what the pro-milk ads would lead you to believe, the whole “strong bones” thing is a lot more complicated than that. There are three fallacies when it comes to the dairy-calcium-bones triad:
- Building strong, healthy bones depends only on calcium.
- Your calcium
intake
is the only thing that matters. - Dairy is the only good source of calcium.
Let’s break these down one at a time.
There’s no denying that calcium is important for bone health—calcium is the substance that gives bones strength, like bricks do for a building. But bones need more than just calcium to grow and stay strong. Vitamin C, vitamin D
3
(technically a hormone), and vitamin K, along with minerals like magnesium and phosphorous, all play important roles in bone development.
Your hormones and inflammatory status also play a role in bone health—a fact that should not surprise you at this point. Chronically elevated blood sugar and cortisol levels and systemic inflammation all accelerate bone breakdown and inhibit the formation of new bone cells.
If the first fallacy is thinking that bone health is all about calcium, the second is believing that our
intake of calcium
is all that matters. If this were true, then how do you reconcile this:
The United States has one of the highest rates of osteoporosis in the world, despite having one of the highest calcium intakes.
It makes no sense ...
unless there’s more to the story than how much calcium we’re taking in.
And there is: It’s also about how much we’re able to absorb and retain.
