It’s not possible to self-diagnose lactose intolerance. This includes the tests you could find on the Internet, as these tests are not scientifically validated.

To be sure, lactose intolerance must be diagnosed. The diagnosis of lactose intolerance is solely performed under strict medical control with an ad hoc hydrogen breath test. This test includes an oral challenge with a standard dose of lactose (usually 20 to 50 g) followed by the detection, in the exhaled air, of hydrogen produced by the intestinal flora and by the occurrence of one or several/many of the following symptoms: bloating, diarrhea, and flatulence.

Often, lactose intolerance is self-diagnosed by individuals who experience intestinal discomfort after the consumption of dairy products. When they undergo the correct medical diagnosis, only 50% of individuals with self-diagnosed lactose intolerance see their condition confirmed. The severity of symptoms is generally over-reported with self- diagnosis.

Nevertheless, the diagnosis of lactose intolerance should not rule out any other underlying digestive pathology.

Sources:

• Hermans et al. Am J Gastroenterol 1997;92:981-4.
• Nicklas et al. Nutrition Today 2009;44:222-7.
• Suarez et al. N Engl J Med 1995;333:1-4.

Excessive sugar intake is a public health problem. Sweetened foods are often preferred by children, who consume them a lot in result. Concerns that sweetened dairy foods are contributing to excessive sugar intakes, are apparently a misconception. This review summarizes the available data in different European countries, V. Azaïs-Braesco et al. show that total and added sugars are high, especially in children. But sweet products and beverages are the major contributors to added sugar, whereas yogurt is a minor.

Too much added sugars in children

High sugar intake is associated with an increased risk of several diseases, as obesity and metabolic disorders. Numerous countries consider public health policy measures or regulations to counteract excessive sugar intake, especially in children. The authors based their work on the data from 11 representative surveys in Europe. The results showed a relatively higher total sugars consumption in children (16 to 26 % of total energy intake), than in adults (15 to 21 % of energy). Added sugars also represent a higher intake proportion (11 to 17 %) in children than in adults (7 to 11 %).

Low sugar contribution from yogurt

While more than 50% of total sugars and 66% of added sugars or non-milk extrinsic sugars (NME)* in children’s diets come from sweet products (cakes, sweets, etc.) and drinks. Yogurt accounts for only 1–8% of total sugars intake and 4–9% of added or NME sugar, depending on country.

To learn more, read the original article.

* Non-milk extrinsic sugars include: table sugar, honey, glucose, fructose and glucose syrups, sugars added to food and sugars in fruit juices.

Source: Azaïs-Braesco V et al. Nutrition Journal 2017;16:6.

There is a difference between these two situations.

In both cases (lactose maldigestion and intolerance), only a fraction of lactose is digested. Non-digested lactose enters the colon.

For some individuals, the bacterial fermentation of non-digested lactose in the colon results in one or many symptoms such as bloating, diarrhea, and flatulence. This is called lactose intolerance. Thus, lactose intolerance is lactose maldigestion that results into one or many of these symptoms.

Moreover lactose intolerance concerns very few people, whereas lactose maldigestion concerns 70-75% of the world population.

Sources:

• Adolfsson et al. Am J Clin Nutr 2004; 80: 245-56.
• Misselwitz et al. United European Gastroenterol J 2013; 1: 151-9.
• Szilagyi et al. Can J Gastroenterol Hepatol 2015; 29: 149-56.

Lactose intolerance is the inability to digest lactose that results in intestinal discomfort such as bloating, diarrhea, and gas. However, these symptoms are not specific to lactose intolerance and can be associated with psychological factors, such as stress and emotional trauma, or intestinal dysfunctions occurring, for example, during infection or malnutrition.

It is important to remind that lactose intolerance is not a disease but a condition. It means that it is not deleterious for your health. It is also important that lactose intolerance shall not be confused with cow’s milk protein allergy.

Sources:

• Crittenden et al. J Am Coll Nutr 2005; 24: 582S-91S.
• Luyt et al. Clin Exp Allergy 2014; 44: 642-72.
• Misselwitz et al. United European Gastroenterol J 2013; 1: 151-9.

To provide an up-to-date picture of the knowledge in this field, a team from the University of Navarra, at Pamplona, in Spain, conducted a systematic review, which highlights several benefits of yogurt consumption for weight gain and metabolic syndrome.

Yogurt and its encouraging results within a half century of research

The Spanish team focused its research on prospective studies published in the past 50 years (from 1966 to June 2016), which examines the association of yogurt consumption and weight gain, the risk of overweight/obesity or a metabolic syndrome development.

The authors found that in general yogurt consumption is associated with a lower increase in waist circumference, risk of overweight /obesity, and lower metabolic syndrome risk. Their conclusion was that yogurt intake as a part of a healthy diet may contribute to a reduction in adiposity indexes and the risk of metabolic syndrome, as consistently suggested by previous prospective cohort studies.

The overall result of this research work showed that yogurt consumption was inversely associated with weight gain and metabolic syndrome development.

To learn more, read the original article.

Source: Sayon-Orea C et al. Advances in Nutrition 2017;8:146S-154S.

Lactose maldigestion is the difficulty to digest lactose, a type of sugar naturally found in milk and dairy food. Lactose maldigestion concerns most people in the world. It is due to the normal reduction of the activity of lactase, the enzyme that transforms lactose into glucose and galactose, both simpler sugars used by our body for energy and various functions. Lactose maldigestion appears after weaning, when the activity of lactase begins to naturally decline.

For most individuals, this lactose maldigestion produces little or no symptoms. Lactose maldigestion varies between different populations and on whether dairy products are consumed during adulthood. Lactase activity decline is more common in people of Asian,

African, South American, Southern European, and Australian Aboriginal heritage than in people of Northern European (Scandinavia, the British Islands and Germany) descent.

Sources:

• Adolfsson et al. Am J Clin Nutr 2004; 80: 245-56.
• Szilagyi et al. Can J Gastroenterol Hepatol 2015; 29: 149-56.

Lactose is the principal sugar (or carbohydrate) naturally found in milk and dairy. Lactose is composed of glucose and galactose, two simpler sugars used as energy directly by our body. Lactase, an enzyme, splits lactose into glucose and galactose.

Human milk contains 7.2% of lactose (only 4.7% of lactose in cow’s milk), which provides up to 50% of an infant’s energy needs (cow milk provides up to 30% of an infant’s energy needs). Although glucose could be found in several types of foods, lactose is the only source of galactose.

Galactose has various biological functions and serves in neural and immunological processes. Galactose is a component of several macromolecules (cerebrosides, gangliosides and mucoproteins), which are important constituents of nerve cells membrane. Galactose is also a component of the molecules present on blood cells that determine the ABO blood types.

According to more recent studies, lactose may play a role in the absorption of calcium and other minerals such as copper and zinc, especially during infancy. Moreover, if it is not digested in the small intestine, lactose may be used by the intestinal microbiota (the microorganism population that lives in the digestive tract) as a nutrient (prebiotic). Lactose and other milk sugars also promote the growth of bifidobacteria in the gut and may play a life-long role in countering the aging-associated decline of some immune functions.

Sources:

• Amaretti et al. Appl Microbiol Biotechnol 2006; 73: 654-62.
• He et al. Eur J Clin Invest 2008; 38: 541-7.
• Kobayashi et al. Am J Clin Nutr 1975; 28: 681-3.
• Lukito et al. sia Pac J Clin Nutr 2015; 24 Suppl 1: S1-8.
• Vandenplas et al. Asia Pac J Clin Nutr 2015; 24 Suppl 1: S9-13.
• Venema et al. International Dairy Journal 2012; 22: 123-40.
• Vulevic et al. Br J Nutr 2015; 114: 586-95.
• Ziegler et al. J Pediatr Gastroenterol Nutr 1983; 2: 288-94.

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Unlike for cardiovascular disease, the associations between dietary fats and the risk of diabetes have been less investigated. In this prospective analysis in individuals with high cardiovascular risk, Marta Guash-Ferré et al. found an increased risk of type 2 diabetes (T2D) for cheese and butter intakes, and a reduced risk of T2D for whole-fat yogurt.

Type 2 diabetes and animal fats: few clear evidence

Type 2 diabetes (T2D) is on the rise, with more than 415 million adults worldwide suffering from it, and is estimated to increase up to 642 million in 2040.

Because animal fats are rich in saturated fatty acids, their consumption are generally discouraged, as in the 2015 dietary guidelines for Americans, in favor of vegetable fats. However, some studies have shown that each type of saturated fatty acids are not equal, and need  a further research based on the nature of the food.

Thus the aim of the prospective PREDIMED (PREvention con DIeta MEDiterranea) study was to compare the health effects of Mediterranea diet vs control diet in 3.349 individuals. Previous PREDIMED study demonstrated that high vegetable dietary pattern decrease the risk of T2D.

Consuming butter, but not yogurt, may increase the risk of type 2 diabetes

At the baseline, there was no link between saturated fat or animal fat intake and the  T2D occurrence. But after a 4.3 years follow-up, the risk of T2D appears increased in people with the highest uptake of saturated or animal fats. .

However, all saturated or animal fat sources didn’t show the same effects. There were slight differences between several dairy food products, for example whole-fat yogurt consumption was associated with a lower risk of T2D, whereas butter and cheese intake showed the opposite. These results confirm that health effects of fatty acids depend on the type of food. The findings may provide a deeper insight into the recommendations for dietary guidelines, regarding the type of dietary fat to be consumed at a population level.

To learn more, read the original article.

Source : Guash-Ferré M et al. American Journal of Clinical Nutrition 2017;105:723-735.

A child’s taste preferences, which will determine eating habits later in life, are shaped by experience, and it is important to repeat exposure to healthy foods. This was one of the messages from Dr. Julie A. Mennella (Monell Chemical Senses Center, Philadelphia), during her talk at the YINI symposium, “Sweet & sour tastes: from inborn responses to contextual learning in foods ”, as part of the 4th International Conference on Nutrition & Growth (Amsterdam, March 2-4 2017).

The preference for sweetness is innate

Food choices are influenced by our taste preferences. These choices, for example for a diet with little variation, in turn influence the risk of many chronic diseases, which is why it is important to understand these taste preferences. It was Charles Darwin (1877) who first observed that children had their own set of taste preferences, different to that of adults. We now know that the marked preference for sweetness is an innate characteristic. It then fades during adolescence, Dr. Mennella explained.

For the sensory system, the innate attraction of sweetness is interpreted as a sign of a source of energy. A sweet taste can mask the expression of pain. And it really is sweetness and not sugar, because the same observations can be made with low-calorie sweeteners, the specialist continued. Sweetness can also mask the unpleasant taste of a food.

Does a preference to sour tasting foods indicate a more varied diet?

Studies on sour taste  are more recent. They show that unlike sweetness, acidity does not appeal to either group’s taste as much. Nonetheless, children prefer a higher level of acidity than adults. Children who like acidity seem more open to variety, are more likely to eat fruit voluntarily, and are less afraid of trying new foods.

Learning to like healthy food

Dietary history shapes food preferences. Family influences play an important role in this process. Most children do not get the experience they need to learn to enjoy healthy foods. So the focus must be placed on the family, because children develop their preferences before the age of 2. It is important to expose the child regularly to healthy foods (such as natural yogurt, fruit and vegetables) so that they learn to like them, Mennella concluded.

Key points to note

• The attraction to sweetness is innate and more marked in children than adults
• Food preferences are formed by dietary history
• Repeated exposure to healthy foods such as yogurt, fruit and vegetables enable children to learn to like healthy food, encouraging better dietary habits later in life.

Source: YINI Symposium “How yogurt could improve health in children” – 4th International Conference on Nutrition & Growth (Amsterdam, March 2-4, 2017)