The geneticist tells Cecilia Lindgren that every time he gives a talk on obesity, someone in the audience raises their hand to suggest that the solution is easy: eat less. Then, the spontaneous on duty usually adds a derogatory comment: fat people are simply lazy people who lack the willpower to not gorge themselves on junk food. Lindgren, director of the Oxford University Big Data Institute (UK), snorts at this general idea. His team has identified a multitude of genetic variants associated with a greater predisposition to accumulate fat in different parts of the body. Added to other environmental factors, these genes can determine the appearance of cartridge belts or a good “beer belly”, explains Lindgren, born in Gothenburg (Sweden) 48 years ago. The geneticist traveled to Reykjavík (Iceland) on May 19 to give a conference at the headquarters of the local company deCODE Genetics, to which EL PAÍS attended at the invitation of the parent company, the American pharmaceutical company Amgen.
Ask. You insist that obesity is not the result of a lack of will.
Response. It is not.
P. Nor is it a choice.
R. No. I think no one would choose to be obese. Genetic studies tell us that obesity is regulated by feelings of satiety and hunger. We live in an environment with excess calories. If you are much hungrier and don’t fill up when you eat, you are going to eat more at all hours. There is a misconception that they are people who just sit back and gorge themselves. There are always photos of very fat people eating five McDonald’s hamburgers, but the truth is that it is enough to eat an excess of 200 calories a day to gain about three kilos a year. It doesn’t sound like much, but if you do it every year you’ll suddenly be really fat. So I don’t think it’s a choice.
P. How many genetic variants are associated with obesity?
R. Currently we know about 3,000.
P. So there is no such thing as an obesity gene.
R. No, there is not just one. Stephen O’Rahilly, from the University of Cambridge, has investigated diseases caused by just one or two serious mutations in a gene, diseases in which patients cannot stop eating. It is called hyperphagia and is due to the disruption of the neuroendocrine regulation of satiety and hunger. And this is what we see in other people, although not in such a brutal way. In my team we have found two variants in about 6,400 people in the United Kingdom and each variant represents an excess of between seven and 10 kilos in the weight of an adult.
P. Its alot.
R. We speak of a great effect on many people. It is important to underline that we are not victims of our DNA, but we are born with a predisposition. It is essential that these people know why they have to work so hard to maintain a healthy weight.
We have found two genetic variants that each represent an excess of between seven and 10 kilos in the weight of an adult
P. In his field we talk about the obesogenic environment. What exactly?
R. An obesogenic environment is one in which there is food everywhere and at all times. It’s unhealthy food and it’s always close at hand, which means if you’re hungry, you just eat more. In the 1960s, there was alcohol and tobacco on the tables in the rooms. Today we would never do that, because we know it is a mistake. In the 2000s there were French fries and bagels on the tables. Now people are more and more aware and there is more fruit and mineral water. People are starting to understand that you don’t have to have food everywhere and at all times.
P. Is eating 500 calories of bananas the same as eating 500 calories of ice cream?
R. There is a great scientist in Cambridge, Giles Yeowho has written a book called Why calories don’t count. I don’t completely agree, but you’re right that if you put 500 calories of bananas on one plate and 500 calories of ice cream on another plate, the bananas would weigh about five times as much as the ice cream. They do not count only the calories, but the amount of food that you are going to eat. If you eat all those bananas, you’re going to be full for a much longer time. If you eat 500 calories of ice cream, you’ll be hungry again an hour later. It is very high in calories, but it does not fill you up. In food, the weight, the amount of fiber, the consistency also matter…
P. As the rich kids get thin, poor children get fat increasingly. The gap in childhood obesity is growing.
R. It depends on the countries. The reason I’m concerned about childhood obesity is because as an adult it’s hard to break the cycle and be thin. And there is great discrimination against overweight and obese people. 24% of health workers think that obese people are less deserving of treatment. And 24% of teachers believe that obese children are dumber, so they give them lower grades, even if they do well on exams.
24% of teachers believe obese children are dumber, so they get lower grades
P. Body mass index plays an important role in socioeconomic status.
R. Yes, there is a strong correlation between socioeconomic status and body mass index. Poor children are more likely to be obese. Poor people often have difficulty accessing adequate food. It is very expensive to buy cereals, fruits and vegetables, compared to buying high-calorie food.
P. If you have little income, you are more likely to be obese. And if you’re obese, you’re more likely to be low-income.
R. I would be careful and say that there is a correlation, not that one variable is the cause of the other.
P. A study with 120,000 participants in the United Kingdom, published in 2016, stated that overweight people, especially women, are at a disadvantage; and that tall people, especially men, have an advantage.
R. Yes, but it is a correlation, it does not imply that one variable is the cause of the other.
P. You argue that obesity is “a brain problem.”
R. It is largely regulated through the brain.
P. It is in the brain and in our pockets, because it also depends on whether you have more or less money.
R. Yes, the question is what dictates that this be so. Obviously, if you’re rich, you can go to a fancy gym and you can afford to buy all kinds of healthy foods. And education also influences: if children have parents who talk to them about the importance of taking care of their health.
P. You state that 10% of the population no risk of being severely obese.
R. People with a strong predisposition to obesity, with all the genetic variants, could weigh about 20 kilos more than another person of the same age, sex and height. But there are other people who are lucky in that lottery and are not at risk of obesity: they have a predisposition not to be hungry.
P. With all this genetic information about obesity, is it possible to develop effective drugs? Or with 3,000 genetic variants involved is it impossible?
R. Now I am very excited, because there is a drug on the market that people lose 15% of your body weight [la semaglutida, relacionada con el gen GLP-1]. And there is another drug, the setmelanotide, which acts on a regulatory mechanism of hunger and satiety that Stephen O’Rahilly and I found both in common types of obesity and in diseases caused by mutations in a single gene. This drug is going to be extremely important. There is an investigation of Karine Clement [experta en obesidad de la universidad parisina de La Sorbona] and other colleagues from France in which they see people who lose between 12% and 15% of their weight in a few weeks, with this drug. We will eventually have drugs that work for everyone, but we need more drugs for different scenarios. We are already seeing the effect that taking a pill can have, but this does not mean that you have to eat chips and shout “Hooray! I don’t have to worry anymore!” These pills will help you control the situation, which is wonderful.
It is important that obesity is treated as a disease, so that people take it seriously
P. What is the role of the food industry in the obesity epidemic? Do you think it’s like the tobacco industry?
R. I believe that food eaten in the right amount and at the right time is not dangerous. Tobacco, on the other hand, is dangerous even if you smoke little. I believe that the food industry should have a role [en la lucha contra la epidemia de obesidad], especially when declaring its ingredients. Many governments are working to make labels simpler so that people can understand what foods are healthy. And the role of the industry is key there.
P. The obesity is an illness?
R. Yes, according to the World Health Organization, it is. And I think it is important that it be treated as a disease, so that people take it seriously, because it is affecting people and also the economy.
P. In Spain it was learned in 2018 that Coca-Cola had paid eight million euros to medical and scientific associations. What do you think about the food industry putting money into science?
R. We have discussed this issue at my institute and it is a very difficult issue. Outside companies should not be able to fund research and have a say in the results. No company can pay me to say that their product is great, because that’s advertising, not science. If they want to fund my research and I find that their product has a harmful effect, I must be able to publish it. I should also post it if I don’t see any effect or even if it has a positive effect of course. Science has to be critical and free.