Many believe that milk and other dairy or ‘lactose-free products are healthier, but they are only necessary if you have an intolerance to this type of sugar. Know the advantages and disadvantages of opting for its intake.
In recent years, the consumption of milk and ‘lactose-free products have become popular, with growth estimates of 27% each year. Logically, it is not because there is a 27% increase in the incidence of pathologies related to the digestion of lactose. Still, it responds to other motivations: many people who do not have problems digesting this sugar opt for products ‘without thinking that they are healthier.
This is reflected by AECOC, which indicates that 75% of these voluntary consumers choose lactose-free products because they consider them “healthier” and “more digestive.” However, this is unfounded. And to understand this statement, we will try to clarify what lactose is and why its intake does not affect people without intolerance, and how it does negatively harm people with digestive problems.
What is lactose
Lactose is a carbohydrate simple, that is, what is commonly known as ‘sugar’. It is formed by the union of two simpler sugars (called monosaccharides), glucose and galactose.
The milk contains about 4.7 grams of lactose per 100ml. It is important to note that, despite being a simple sugar, the WHO does not consider it a free sugar but an intrinsic one when it is found in milk and dairy products. Therefore, it does not have harmful effects on health and does not fall within the sugars group that we have to limit in our diet.
Adverse effects of lactose consumption
Under normal conditions, lactose is digested in the small intestine. The cells that line the intestinal wall (enterocytes) produce the enzyme β-galactosidase (also known as lactase), which breaks the bond between glucose and galactose. These molecules are smaller than lactose and can be absorbed into the blood, which carries them to the tissues to serve as an energy source.
According to a nutrition Specialist the intestinal cells of people with lactose intolerance cannot secrete this enzyme, hypolactasia (lactase deficiency) appears. In this way, the lactose is not digested and reaches the large intestine intact. The presence of lactose in this area of the digestive system has a double effect:
- It attracts water, which passes from the blood to the intestinal lumen. The water dilutes the stool and produces typical diarrhea.
- It serves as a substrate for the intestinal microbiota. Bacteria ferment it and produce metabolites and gases. These gases are what cause bloating and flatulence.
Types of lactose intolerance
In very few cases, lactose intolerance appears from birth. It is known as congenital primary lactase deficiency and is the most serious since the newborn does not tolerate milk.
However, lactose intolerance that occurs after weaning is a normal physiological condition. There is a progressive reduction in this enzyme production until only 10% of the initial one is maintained. It is estimated that between 66% and 75% of the world’s population is lactase deficient (with large variations depending on ethnicity). In Spain, this condition affects 34% of the population.
Finally, there is a type of secondary deficit that appears when there is a pathology in the small intestine, for example, gastroenteritis. Once the disease is over, the enterocytes usually regain the ability to produce lactase in more or less time.
It should be clear that lactose intolerance is not a food allergy. Allergies involve the immune system. When the person is exposed to the allergen, the adverse reactions can be very serious and life-threatening: this is what happens in an allergy to milk proteins.
However, in food intolerances, the negative effects occur at the intestinal level, and although they can be annoying and limiting, they do not represent a vital compromise. Therefore, lactose intolerance is not a milk allergy.
Pros and cons of drinking milk and ‘lactose-free products
Before going to buy milk’ lactose-free or other dairy or ‘no lactose,’ need to know if there is a physiological condition that justifies it. Many people self-diagnose as allergic or intolerant to food and eliminate it from their diet for no reason. A recent study published in the JAMA Network Open estimated that only half of the people who considered themselves allergic suffered from this condition.
This, far from improving your health, can pose a double problem: food groups are eliminated from the diet and, if there is a digestive pathology, it can make the diagnosis difficult and delay the therapeutic approach.
It is very positive that ‘lactose-free products are flooding the market because that means that they are accessible to people with lactose intolerance (real and diagnosed) at a reasonable price (although it is still higher than their conventional counterparts). But in the case of the general population, their intake is not justified; they will not provide any benefit, and, on the contrary, it can be a problem.
And it is that, in addition to the obvious dietary restrictions, the ability to produce lactase is adaptive. If there is lactose, we make the enzyme; if there is no lactose, the lactase disappears. That is, we can end up being lactose intolerant simply by not exposing ourselves to it.
Also, the consumer without intolerance who purchases these dairy products ‘without’ will be paying approximately 33% more for a product that they do not need.