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Obesity and malnutrition An international perspective of the paradox
Gianluca TognonSahlgrenska Academy
www.gianlucatognon.com
The undernutrition and obesity paradox
• Obesity runs highest among the lowest income groups• Undernutrition and obesity often occur together within the same
community, the same family, and sometimes within the same person
• Obesity in people with very low food security becomes understandable in the context of the food supply
• A person can easily gain weight and lose nutrient status when the most affordable and available foods provide abundant calories but few nutrients, such as refined grains, sweets, inexpensive meats, oils and fast foods, which provide too many calories with too few nutrients
• People who have gone hungry in the past and whose future meals are uncertain may overeat when food or money becomes available
MALNUTRITION
ACTIVITY 1
Hunger?Malnutrition?Undernutrition?Undernourishment?Food security?Food insecurity?
• Hunger: A condition in which people lack the required nutrients for fully productive, active and healthy lives. It can be short-term/acute or longer-term/chronic, and has a range of mild to severe effects. It can also result from insufficient nutrient intake or from people’s bodies failing to absorb the required nutrients (hidden hunger). It can also result from poor food and childcare practices.
• Malnutrition: A physical condition in which people experience either nutrition deficiencies (undernutrition) or an excess of certain nutrients (overnutrition).
• Undernutrition: The physical manifestation of hunger that results from serious deficiencies in one or several macro- and micronutrients. These deficiencies impair body processes, such as growth, pregnancy, lactation, physical work, cognitive function, and disease resistance and recovery. It can be measured as weight for age (underweight), height for age (stunting) and height for weight (wasting).
• Undernourishment: The condition of people whose dietary energy consumption is continuously below the minimum required for fully productive, active and healthy lives.
• Food security: A condition that exists when all people at all times are free from hunger. It has four parts, which provide insights into the causes of hunger (FAO): 1. availability: the supply of food in an area; 2. access: a household’s ability to obtain that food; 3. utilization: a person’s ability to select, take in and absorb the nutrients in food; 4. stability.
• Food insecurity, or the absence of food security, implies either hunger resulting from problems with availability, access and use, or vulnerability to hunger in the future.
The world food supply• By all accounts, today’s total world food
supply can abundantly feed the entire current population
• Wheat and corn, staple foods of many nations, are abundant
• Adequate supply alone, however, does not ensure that all people will receive adequate food
• The political will to do so is also required
Threatens to world food production and distribution
• Hunger, poverty and population growth• Loss of food-producing lands• Accelerating fossil fuel use• Atmosphere and global climate changes,
droughts and floods• Ozone loss from the outer atmosphere• Water shortage• Ocean pollution
• The Millennium Development Goals are eight international development goals officially established following the Millennium Summit of the United Nations in 2000
• The goals are:– Eradicating extreme poverty and hunger – Achieving universal primary education– Promoting gender equality and empowering women – Reducing child mortality rates – Improving maternal health– Combating HIV/AIDS, malaria, and other diseases– Ensuring environmental sustainability– Developing a global partnership for development
The millennium development goals
The importance of proteins
• Foods of animal origin are the best protein sources, but they tend to be expensive, not always available, or prohibited by religious practices
• Staple vegetable foods can be complemented with other vegetable foods such as legumes
• Corn and black bean combination (three parts of dry corn and one part of dry beans) provides proteins in a proportion of about 6:4 and have an excellent aminoacid composition which allows adequate growth and function
• Energy density can be increased adding sugar and oil or other fats
Food prices• After declining in real terms throughout the 1980s and
1990s, international food prices began rising in 2002 in an apparent reversal of this long-term trend
• By 2011, the FAO Food Price Index reached more than double its level during 2000-02
• Sugar, oils and cereals showed the sharpest increases in 2010 and early 2011
• Meat prices have risen least and have shown less marked fluctuations
• Dairy prices have been below the FPI average since late 2010 and have fallen markedly in recent months
Reasons for food price increase• Population growth • Higher per capita incomes• Urban migration and associated changing
diets in developing countries• Weather-related production shocks• Rising demand for biofuel feedstocks• The role of speculative trading as a factor
underlying price volatility has also been debated
Will global agriculture to keep pace with growth in demand?
Undernutrition• A major health problem, especially in developing
countries• Adequate water supply, sanitation and hygiene,
are important for preventing infections and diarrhea
• Repeated or persistent diarrhea on nutrition-related poverty and the effect of undernutrition on susceptibility to infectious diarrhea are reinforcing elements of the same vicious circle, especially amongst children in developing countries
Underweight in children < 5 yrs
Biologic and environmental causes• Maternal malnutrition before and/or during
pregnancy (underweight newborn)• Infectious diseases (diarrheal disease, measles,
AIDS, tuberculosis and others)• Overcrowded and/or unsanitary living conditions
(which increase the likelihood of infections)• Agricultural patterns, droughts, floods, wars and
forced migrations
Social and economic causes• Poverty• Ignorance• Inadequate weaning practices (withdrawal of
breastmilk or inadequate nutrient composition)• Social problems (child abuse, maternal
deprivation, abandonment of the elderly, alcoholism, drug addiction)
• Cultural and social practices (food taboos, food and diet fads)
Differences between countries
• Undernutrition is far more debilitating in some places than in others
• In the industrialized countries, hungry people lack 130 kcal per day on average, while in the poorest countries, the daily food deficit is more than three times that, i.e. 450 kcal/day
• Most of the countries with the most extreme depth of hunger (> 300 kcal/person/day) are located in Africa and many of these face extraordinary obstacles such as conflicts or recurrent natural disasters
Consequences of chronic hunger
• Tens of thousand people die of undernutrition every day. Most do not starve to death, they die because their health has been compromised by dehydration from infections that cause diarrhea
• Undernutrition reduces mental and physical development in children and makes people susceptible to potentially fatal infections
• Consequences of unrelieved hunger include stunted growth, poor learning, extreme weakness, clinical signs of protein-energy malnutrition (PEM), increased susceptibility to disease, loss of the ability to stand or walk, premature death
ACTIVITY 2
Policies for malnutrition prevention, focus on:- Governments/International agencies- Private sectors- Civil society- Health professionals
Interventions for malnutrition prevention• Improved water supply, sanitation and
hygiene.• Health education for a healthy diet• Improved access, by the poor, to adequate
amounts of healthy food• Ensuring that industrial and agricultural
development do not result in increased malnutrition
Education• Girls and women should be specially targeted in
educational and developmental programs• Education programs must also be devised for
community leaders, civic action groups, and the community as a whole
• Such programs should emphasize: – promotion of breast-feeding– appropriate use of weaning foods– nutritional alternatives using traditional foods– personal and environmental hygiene– early treatment of diarrhea and other diseases
Focus on women• Many societies around the world undervalue females,
depriving girls of nutritious foods and giving them less education and fewer opportunities than are given to boys
• Malnourished girls become malnourished women in poverty who bear sickly infants who cannot fend off the diseases of poverty
• Many such infants succumb within the first years of life• Seven out of ten of the world’s hungry people are women
and girls, yet they receive only about half of the available food aid and must use it to feed their children as well as themselves
Women and hunger: 10 facts (WFP)
1. Women make up a little over half the world’s population but in many parts of the world, especially in Asia and South America, they are more likely to go hungry than men
2. Following natural disasters, women and girls suffer more from shortages of food3. Research confirms that putting more income in the hands of women yields beneficial
results for health, education and child nutrition4. Closing the gender gap in agriculture by giving women farmers more resources could bring
the number of hungry people in the world down by 100-150 million people5. Surveys in a wide range of countries have shown that women provide 85-90 % of the time
spent on household food preparation6. Women in Africa work an average of 50% longer each day than men7. Worldwide, for every 100 boys out of school there are 122 girls. But in some countries the
gender gap is much wider. For every 100 boys out of school in Benin there are 257 girls, in Yemen 270, in Iraq 316, and in India 426
8. Educated mothers have healthier families. Their children are better nourished, are less likely to die in infancy and more likely to attend school
9. Around half of all pregnant women in developing countries are anaemic. Iron deficiency causes around 110,000 deaths during childbirth each year
10. Malnourished mothers often give birth to underweight babies who are 20% more likely to die before the age of five. Up to 17 million children are born underweight every year
Hunger in developed countries
• In developed countries (including the USA), the primary cause of hunger is food poverty
• People go without nourishing meals because they lack sufficient money to pay for food and other necessities, including medicines
• Food poverty likelyhood increases with problems such as abuse of alcohol and other drugs, mental or physical illness, depression, lack of awareness of or access to available food programs, and reluctance of people to accept what is perceived as charity
Consequences• Adults may skip meals or cut their portions• They may be forced to break social rules, stealing
from markets, consuming pet foods, or even harvesting dead animals from roadsides or scavenging through garbage cans
• Such foods may be spoiled or contaminated and inflict dangerous foodborne illnesses on people already bordering on malnutrition
• Children in such families sometimes go hungry for an entire day until the adults can obtain food
Supplemental Nutrition Assistance Program (SNAP) in the US
• Administered by the USDA, it provides assistance to more than 20 million people half of which are children
• Eligible households receive coupons or debet cards similar to credit cards through state social services or welfare agencies
• Recipients can use the coupons or cards like cash to purchase food and food-bearing plants and seeds, but not to buy tobacco or other non-food items
• Although this program helps millions, many millions more are thought to be eligible to receive them
Second Harvest• Each year, enough food to feed 49 million people is wasted • Food recovery programs collect and distribute good food that
would otherwise go to waste and the donators qualify for tax deductions for their donations
• Concerned citizens in many communities work through local agencies and churches to help deliver food to hungry people
• National food recovery programs have made a dramatic difference• In the US, Second Harvest, provides more than 1 billion pounds of
food to 45,000 local agencies that feed over 25 million people a year
• Many food-insecure people rely on these sources of food for survival
Protein-Energy malnutrition• It results when the body’s needs for protein and energy
fuels are not satisfied by diet• It can be primary (inadequate food intake), or secondary
to other diseases that lead to low food ingestion, inadequate nutrient absorption or utilization, increased nutritional requirements, and/or increased nutrient losses
• It is the most important nutritional disease in developing countries because of its high prevalence and relationship with child mortality rates, impaired physical growth and inadequate social and economic development
Body Mass Index Protein-Energy malnutrition
≥ 18.5 Normal
17.0 – 18.4 Mild
16.0 – 16.9 Moderate
< 16.0 Severe
Classification of protein-energy malnutrition based on BMI
Prevention and control• Rates of malnutrition have declined rapidly in countries that
have reduced poverty and have invested in health, nutrition, education and the social sector
• The strategies for prevention must follow a multisectorial approach involving all levels of food security, preventive medicine, education, social development and economic improvement
• Effective control and prevention can be achieved only through sustained long-term political commitments and actions aimed at eradicating the underlying causes of malnutrition
• Physicians, nutritionists, health personnel, social workers and educators can and must play an active role
OBESITY
Background• Obesity is caused by a chronic energy imbalance involving both
dietary intake and physical activity patterns• A change in diet towards highly refined foods and meat as well
as dairy products containing high levels of saturated fats has been occurring globally since the middle of the 20th century
• The shift from individual to mass preparation lowered the time price of food consumption and produced more highly processed food (with added sugar, fats, salt and flavour enhancers) and marketed them with increeasingly effective techniques
What’s obesity?• Obesity if defined as having a BMI ≥ 30 kg/m2
• BMI is a good, but not perfect, surrogate for body fatness• People with an ”obese” BMI may have a normal amount of body
fat and a large muscle mass, whereas others with a ”normal” BMI may have excess adiposity and reduced muscle mass
• Measuring the circumference of the waist can provide an additional check (cut-offs: 88 cm in women, 102 cm in men)
• Waist circumference is highly correlated with the amount of intraabdominal or visceral fat, which is an independent predictor of increased risk for diabetes, hypertension, dyslipidemia and ischemic heart disease
• The combination of waist circumference and BMI can be useful in assessing health risk
Health consequencies• The prevalence has been increasing worldwide over
the past 30 yrs in both rich and poor countries• By 2050, 60% of men and 50% of women could be
clinically obese• The risks of developing type 2 diabetes, heart
disease and cancer all increase as BMI will increases• Mortality increases gradually above a BMI of 25
kg/m2 with a sharper increase above a BMI of 30 kg/m2
Environmental factors connected with weight gain
• Smoking cessation• Maternal smoking and diabetes• Breast-feeding• Toxics exposure (endocrine
disruption)
The Heredity of Obesity• It is estimated that up to 40% of variation in BMI is explained
by genetic factors• BMI is highly correlated among first-degree family members,
with an increased relative risk for the development of obesity for a first-degree relative of an obese person
• Single-gene defects have been identified (e.g. in the MC4R, PPAR or leptin genes) although very few individuals with these defects have been identified
• It is likely that obesity is a highly polygenic and complex disorder, resulting from the input of multiple genes, with additional interactions between genes and environment and genes and behavior
The Genetic hypothesis• Genes involved in the regulation of body weight are
estimated to have evolved 200,000 to 1 million years ago, at a time when environmental factors controlling habitual physical activity and food acquisition were dramatically different
• The marked increase in the prevalence of obesity since the mid-1980s cannot be attributed to changes in the gene pool (which require longer period of time) and must be largely a result of alterations in environmental factors
• However, factors others than DNA could be implicated (possible heredity of RNA subtypes, like microRNA)
• Family studies demonstrate that obese parents produce the highest proportion of obese children
• Adoption studies provide another approach for estimating heritability based on the similarity of adoptive childrens’ body weight to that of both their adoptive and biologic parents These studies suggest a stronger role for genetics than for the environment
• Twin studies have been an integral part of the research into the genetics of obesity and they provide stronger support for the effect of genetic factors on BMI, which has been shown to be similar between twins, with the strongest correlation in monozygotic twin pairs. The observation holds true whether twins were raised separately of apart
ACTIVITY 3
Policies for obesity prevention, focus on:- Governments/International agencies- Private sectors- Civil society- Health professionals
Obesity policies• Obesity threatens to have a great impact on public
health worldwide but the mechanisms of its increase in prevalence and its consequences are far less well understood in policy terms
• This lack of knowledge presents a serious challenge to public health policy
• Curbing the global obesity epidemic requires a population-based multisectoral, multi-disciplinary, and culturally relevant approach
• Focus on the built environment and people behaviour is also important
Obesity vs Tobacco control• The associated adverse behaviour is more readily identified for
smoking than for obesity• The major successes of tobacco control have been linkedin to
the application and implementation of a broad range of policies• Obesity control policy is in many ways more complex• The changes needed to reverse the obesity epidemic are likely to
require many sustained interventions at several levels: individual behaviour change, interventions in schools, homes and workplaces as well as sector changes within agriculture, food services, education, transportation and urban planning
• For obesity however, no clear consensus on effective policy or programmatic strategies has been reached
• Successful strategies to rapidly lower obesity rates need to target all age groups and take a life-course approach
An unequal weight• Obesity is a global problem, unequally
distributed between and within countries• In affluent societies excess weight is more
common among socially disadvantaged groups, but the inverse is true in low income countries
• Focusing only on direct action to make people eat more healthily and be more physically active misses the heart of the problem: the underlying unequal distribution of factors that support the opportunity to be a healthy weight
