Mexico City – like the rest of the country – is in the grip of an obesity crisis. While the reasons for this are far from black and white, close analysis suggests that a lack of physical activity could be the main contributing factor.

In 2013, Mexico responded to its (literally) growing problem by introducing taxes on food and drink with a high sugar or fat content, becoming something of an international case study. While this has been successful in raising money for the government, the health impacts of the “sugar tax” are not yet scientifically proven.

The move was prompted by reports such as the 2012 National Survey of Health and Nutrition, which found that in greater Mexico City, almost seven million people were overweight and five million people were clinically obese – a total of 56% of the city’s population of around 21 million people. As hard as it is to compare these numbers with those in other Mexican cities (due to the lack of representative data for smaller cities), we can say that if Mexico City were a state, officially it would be the most overweight state in the entire country.

Between 2000 and 2012, adult obesity has shown a steady upward trend in the capital, where it affected 16% of the city population in 2000, 19% in 2006, and 26% in 2012. In 2012, more women (28%) than men (24%) were found to be obese in central Mexico City, while 35% of children aged five–11 were either overweight or obese.

The consequences of these numbers could be devastating: Mexico’s health ministry has warned that if the problem is not addressed, the life expectancy of future generations will probably go down.



A 16-year-old boy attends a medical consultation at a Mexico City hospital for symptoms related to severe morbid obesity. Photograph: Sipa/Rex Shutterstock

According to the World Health Organisation (WHO), a high body mass index is a modifiable risk factor for developing noncommunicable diseases such as diabetes, cardiovascular diseases and even some types of cancer (endometrial, breast and colon). Children may also suffer an increased risk of developing early markers of cardiovascular diseases and insulin resistance, as well as psychological effects.



In 2012, central Mexico City already had the highest rates of diagnosed diabetes and hypertension in the country – respectively, 10% and 22% of the total population. But high as these rates are, the numbers could rise significantly if the proportion of patients who don’t even know that they are ill is taken into account. Earlier, national figures for 2006 had shown that the prevalence of both diabetes and hypertension almost doubled when undiagnosed rates were added. If statistics follow a similar trend, then Mexico – including the capital – could soon be facing an overwhelming health problem.

Why is the city getting fatter?

Obesity is a complex health issue. While its direct causes are commonly linked to eating behaviour and physical activity, a wide variety of underlying factors can influence individual choices. To gauge some of these factors, the Mexican Institute for Competitiveness developed a tool that uses state-level data to identify risks and opportunities, shedding light on some interesting facts that contribute to a greater understanding of the obesity problem.

While food is an important part of Mexican culture (since 2010, the cuisine has been recognised by Unesco as an “intangible cultural heritage”), the capital was recognised as having the country’s highest concentration of street trade in 2010, almost certainly leading to an increased consumption of food of low nutritional value. But the Federal District was also among the eight states that registered the lowest purchases of goods with a high sugar, fat or salt content.



Surveys have found that few Mexican children exercise regularly. Photograph: Alamy

Even the diets of newborn babies might bear some influence: in Mexico City in 2012, just 9% of babies from zero to six months were breastfed exclusively, compared with 14% of babies in the rest of the country.



However, while the precise nature of the city’s dietary problems is hard to pin down, the picture regarding physical activity is much clearer. Put simply, the Federal District is the most sedentary state in the country.



In 2012, only 33% of children aged 10 to 14 years reported doing any significant form of exercise – dancing, or sports such as basketball and football – over the previous year, while 74% of children said they looked at a screen for more than three hours every day during the week. As for the adult population, last year 29% of workers were employed in sedentary jobs, either working in an office or sitting elsewhere in front of a screen.



The explanation for this chronic lack of exercise probably lies with the urban environment – and the lifestyle that is encouraged – and discouraged – by the city’s structure and dynamics.

A fruit salad stall in Mexico City, where fresh food is sold on the streets alongside less health snacks. Photograph: Alamy

Let’s test some hypotheses:



1. There’s no time to exercise

In 2014, the average person in central Mexico City worked 42 hours a week. This number is slightly above the national average of 41 hours; higher, too, than most member-countries of the International Labour Organisation (ILO) – behind only Turkey, Korea and South Africa.

At the same time, commuting times are too long: in 2009, the city’s secretary of transportation estimated that an “average commuter” took one hour and 21 minutes to reach their destination. If every day, a typical employee spends 11 hours commuting and working, that doesn’t leave much free time to do exercise, cook good food, or spend time with the family.



Both factors could also explain why, in 2012, almost 31% of citizens aged between 15 and 69 in central Mexico City were found to sleep six or fewer hours each night.



2. Traffic blocks an active lifestyle

Between 2007 and 2014, the number of cars in the centre of the city grew considerably, by 39%, despite its population falling by 1.1% over the same period. Such unfettered growth in car use underlines Mexico City’s negative reputation for traffic levels, affecting not only its drivers but those using public transport.

The Mexico City skyline seen from Chapultepec Park, the city’s largest green space. Photograph: Alamy

According to IBM, in 2013 Mexico City was the most painful city in which to commute, factoring in its emotional and economic toll in comparison with 20 other cities around the world. A year later, 43% of the city’s public transport users said that those services were too slow.



In an effort to encourage more active means of transportation, in 2010 the city introduced a bicycle-sharing programme, Ecobici, which to date has almost 176,000 users (equivalent to 3% of the central city’s total population). Likewise, in 2013, 7% of federal funds earmarked for mobility were used to increase pedestrian and cyclist infrastructure. Yet, traffic levels continue to rise.

3. Green spaces are too few and often shut



To an outside observer, it might seem odd that inhabitants of Mexico City have access to infrastructure for physical activity, yet most of them do not use it. By 2014, for example, an estimated 87% of the capital’s urban sprawl had exercise facilities such as gyms and dance academies – the highest concentration in the country.



The amount of green space is more limited. According to the city government, central Mexico City possesses 5.4 square metres of green spaces per inhabitant. The WHO recommends there should be between nine and 16 square metres per inhabitant.

Chapultepec is the city’s most iconic and visited park. However, one third of it opens only from 5am to 8pm, and another section is closed on Mondays for maintenance. The other two big parks, Bosque de Aragón and Bosque de Tlalpan, have even shorter opening hours, closing no later than 6pm every day.

Public health experts blame changes in lifestyle for rising levels of obesity. Photograph: MCT/Getty Images

4. Fear stops residents being more active



While Mexico City has not been as affected by insecurity as other regions, there are signs that crime has influenced its inhabitants’ habits and perceptions when it comes to adopting a more active lifestyle.

In 2013, the National Survey of Victimisation and Perception of Crime found that 32% of respondents avoided walking on the street for fear of becoming a victim of crime. In addition, 82% of respondents said they would not allow their children to go out unattended – which might explain why the city’s children spend most of their free time playing video games, rather than those of the outdoor variety.

A bitter pill

The Mexican government has made many attempts to fight the pervasive weight problem, attracting international attention for its implementation of a national tax of one peso for sugar-sweetened beverages, and an 8% price rise on high-calorie foods such as ice-cream, chocolates and confectionary.

Recently, the house of Congress approved halving the tax of those beverages containing only 5 grams of sugar per 100ml. This measure aims to be an incentive for the industry to provide more healthy options.

Both taxes were introduced in January 2014, and have proven immediately successful as a fiscal measure, at least. In the first year, total income for both taxes exceeded the treasury’s forecast by 76%, collecting almost 32bn pesos.

Preliminary results from a study by the National Institute of Public Health suggest an average reduction of 6% of sugar-sweetened beverages at the end of 2014, in comparison to the trend before the tax was implemented However, up-to-date results from neither this study nor one by the Mexico Autonomous Institute of Technology (ITAM) have been released.

The introduction of these taxes generated a huge polemic nationwide. While the national government regards the policy as a big step forward in the fight against obesity, the food and drinks industry is still coming to terms with the move. Many want a greater proportion of the money raised to be channeled into preventative actions: “Some advocacy groups are requesting doubling the tax rate to enhance reductions in consumption,” says Juan Luis García, a health reporter based on Mexico City.

At a national level, “it is likely that most people have felt the changes in prices, but they are not aware of the reasons,” García adds. “They know that taxed products are more expensive, but not all of them link it with health issues.”



What is abundantly clear is that – even if the sugar tax does prove successful, Mexico City still needs to take action to incentivise people to adopt more active lifestyles.



The city has introduced a machine that rewards squats with tickets for the metro.

Photograph: Andrea Sosa Cabrios/Alamy

The city’s health ministry recently installed exercise machines at metro stations that exchange a certain number of squats for tickets. The current administration has also made efforts to build open, urban gyms – the current total stands at 366 – and rehabilitate public areas for exercising. At weekends, a civic programme called Muévete y Métete en Cintura attempts to guide the population towards more healthy lifestyles and physical activity.



Despite these efforts, however, the data shows that more action is still needed to make the city more suited to active lifestyles. Four critical steps to achieve this could be:



1. Incentivise (with the secretary of labour) the implementation of programmes to promote healthier lifestyles in firms – by facilitating the use of stairs in buildings, or forming agreements with nearby gyms.



2. Increase and improve public spaces to encourage walking. Such a programme would not require huge investment but could start by making streets more welcoming, with better pavements and less street trade.

3. Increase safety measures, adding more lighting and surveillance, to encourage people to exercise in public spaces. An increase in the perceived safety of parks might increase activity levels, especially among children.



4. Strengthen measures to increase the capacity and quality of public transportation, and invite people to walk and cycle more.

Given the urgency and pervasiveness of the national obesity crisis, Mexico City needs to take the lead in promoting healthier lifestyles for its inhabitants.But to achieve this objective, the underlying factors that reduce physical activity and diminish the quality of people’s diets must be addressed.

Mexico City is an engine of economic growth for the country. To ensure that growth is not hampered by declining labour productivity and the increasing economic burden of disease, health should be at the core of the city’s development agenda for years to come.

Fátima Masse is an economist whose research focuses on public health policy and urban development. She tweets @Fatima_Masse