Scientists have long been debating the French Paradox – the biogeographic observation of lower than expected mortality from cardiovascular disease in France despite high consumption of saturated fat, compared to other countries.
Some of them call this paradox an “illusion”, while others debate whether the French diet is consistent with Mediterranean-type diet “famous” secret for health and longevity.
This post is not about clinical aspects of the French paradox concept or the drinking/eating habits of French people, it’s actually all about cheese!
French people eat on average 27 kg of cheese per year per capita, or roughly 75g per day (slightly less than a palm size), but they are still not the biggest cheese consumers in Europe.
Few scientists are offering an interesting, almost amusing theory that French cheese is the magic bullet, explaining the paradox. Whether it’s a joke or a serious attempt to understand the impact of cheese on human health, I let you decide. The idea of writing about cheese was born from general myths and fears of consuming cheese in the midst of the modern hype for veganism and lactose-intolerance craze.
Cheese is arguably one of these products that can’t leave anyone indifferent. It’s either a full-on love story or complete avoidance because of the taste, smell or health/ethical concerns.I switched from ignorance to absolute affection, and later to complete avoidance and careful reintroduction within the last 15 years.
It’s all began with the 1st myth “If you have lactose intolerance, you can’t eat cheese”.
Although I have never been officially diagnosed with lactose intolerance, dairy products, especially cow milk, started to cause mild digestive issues from my early 30th. At that time, my knowledge about lactose was based on a couple of articles published in “health” magazines, so I became convinced to be part of a growing adult population lacking lactase enzyme, which breaks down lactose. Perhaps everyone already knows, but let’s quickly remind us what the exact issue with lactose is. Lactose is just a sugar made up of two simple sugars called glucose and galactose that are linked together by a particular type of bond. So, lactase enzyme need to be produced in high amounts in our small intestines to actually break this specific bond, otherwise lactose will undergo fermentation by bacteria in the gut, causing flatulence, bloating and tummy pain. It seems that we lose this ability to produce lactase with age, but some people actually may have genetic mutations causing lactase deficiency from birth.
To understand the concentration of lactose in cheese, we need to understand the cheesemaking process. But before that, let me stress that lactose content in goat and sheep milk is similar to cow’s milk i.e. between 4-5 %, bringing the 2nd myth “There are less lactose in goat and sheep milk, they are safer”. In essence, milk is just 80- 85% water, containing 4-5 % of fat, 4-5% of lactose, 3-3.5 % of proteins (casein and whey), some minerals and vitamins. Goat and sheep milk have very similar lactose content to cow milk, but they actually have different types of proteins, which we will discuss in more detail.
During the cheesemaking process, added starter culture (bacteria) will typically ferment lactose to lactic acid, lowering the pH (increasing the acidity) as an essential primary reaction. In addition, cheese producers add coagulation agents, or rennet – an enzyme that acts on the milk proteins to aggregate together, forming the curd. Once the curd is formed, whey is drained and the rest of lactose will migrate with it, so the final lactose content becomes really negligible.
At the final stage, the curds are salted, shaped and left to ripen (age) in a controlled environment. As cheese ripens, bacteria break down the proteins and remaining lactose, altering flavor and texture of the final cheese.
Bottom line, if you truly have lactose intolerance, which seems to be less common than widely perceived, you can still tolerate dry, well-aged cheese such as gouda, cheddar, parmesan or delicious corsican tomme cheese. Don’t deprive yourself from this pleasure!
If you are still with me, this is where it starts getting a bit confusing but also very interesting.
Some of your bloating, gas and stomach cramps symptoms may actually be related not to lactose, but to casein intolerance. That was my case, but I only discovered it a couple of years ago through a food intolerance test. It was a real disappointment, given that casein is present in all dairy products, regardless of the lactose amount.
So what is this casein?
Casein is a protein and makes up about 80% of the total protein in milk. Casein protein comes in 4 different variants: alpha-s1, alpha-s2, beta and kappa casein. It’s important because each variant has its own amino acid profile and functional properties as we will see below.
To get things even more confusing, beta casein has A1 and A2 genetic variants (it actually has 12 different types, but these two are used to represent the main types). And A2 type is believed to be the ancestral type of beta-casein. There is a theory proposing that genetic mutation, that gave rise to A1 type protein, occurred around 8000 years ago in European herds, as cows of European descent produce both A1 and A2 beta-caseins, but native Asian or African cows only have the A2 allele. And it’s A1 or a mix of A1 and A2 which seems to be problematic for some of us.
How are they different?
Both A1 and A2 proteins are very similar, composed of 209 amino acids, but the only difference is at position 67 where A1 has histidine amino acid, but A2 has proline amino acid. It doesn’t seem like a big deal, but it’s actually relevant to the way the proteins are digested. In fact, during digestion only A1 produces a peptide called b-casomorphin (BCM-7) after enzymatic reaction at this specific position 67. Caso means casein and the morphine from Morphus, the Greek god of sleep.
BCM-7 is related to the opiate family and may potentially cause various effects on central nervous, digestive and immune systems in some people. For example, in one animal study, BCM-7 has been shown to have an analgesic effect and improved learning function. On the other hand, these bioactive peptides have been suggested to contribute cardio-vascular diseases, type 1 diabetes, skin reaction, to increase mucus production in gastrointestinal tract and to alter gastric motility. And here comes another myth “Cheese is addictive”,which started with recent media excitement jumping on 2015 published research paper by University of Michigan. In this study 120 undergrad students were recruited on campus and asked to complete a list of addictive foods. You would have guessed, cheese was listed in top 10 ranking, but well after pizza, ice cream, fries, chips and cakes – the classic podium of highly processed foods. Media was quick to link this arguable scientific study with activation of brain opioid receptors, concluding that cheese produce a feeling similar to hard drug addiction.
But let’s forget the drama and dig a bit deeper into research, there is some evidence that under normal digestive condition, the opioid peptide BCM-7 is released from A1 but not from A2. Note, that in the USA, the majority of cow dairy products is A1. There is also consistent evidence in rodents and some human population groups that A1 and BCM-7 are proinflammatory and induce immune response. It does alter gastrointestinal transit (causing constipation in children, and diarrhea/or slower transit in some adults) but exact mechanisms behind are still not understood. Another hypothesis suggests that since BCM-7 released from A1 slows down the passage of food through the digestive system (as do other opioids), it provides longer time for lactose fermentation.
Well, it’s an emerging area of research fascinating to follow, it may elucidate some interesting points in the future.
Let’s put aside cows and discuss goat and sheep milks. A lot of people report much better tolerance for goat and sheep products. And for a reason. Both types of milk have similar casein structure (but different from cow’s milk). Interestingly, beta-casein in goat milk exists mainly as the A2 type, so it could potentially be less inflammatory. They both contain significantly less alpha S1 casein, which is associated with allergies. So it’s not just beta A1 vs A2 story, but also alpha-s1 vs alpha-s2 allergy triggers. In addition, fat molecules in goat milk are actually shorter, making it much easier for the body to assimilate.
So, if you suspect casein intolerance, try to play with various types of cheese. Evidence suggests that goat or sheep milk have lower incidences of allergy and intolerances than cow milk, although the precise statistics are unknown. In my case, unfortunately both goat and sheep dairy also trigger digestive issues, however, quantity and concentration matters.
I still occasionally eat goat and sheep cheese in small amounts because a) I just love cheese (perhaps it’s a drug after all); b) I care about my gut bacteria diversity; c) I worry about running short on calcium. Interestingly, it’s all actually down to this controversial protein casein and its ability to bind significant amounts of calcium. Leading us to another myth “All cheeses contain very high amounts of calcium”. But this one we will discuss in the next blog – stay tuned!