Poverty and obesity

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Introduction

Draft:

Poverty and obesity are said to be very closely linked but the relationship is complex. Whilst historically being overweight was predominantly seen in the upper class as a sign of wealth and prestige, today the recent trends show a somewhat different picture. In the USA, some of the highest rates of obesity occur in the poorest population groups and in the UK the trends are similar. The inequality in income resulting in obesity is largely associated with less expenditure on food, decreased diet quality, and energy-dense foods that represent the lowest-cost option for consumers. Cheap palatable foods high in fat, sugar and energy are the result of developments in agriculture and food technology and the shifting ‘nutrition transitition’ now seen in developing countries highlights the need for a greater awareness of diet quality and a need for preventative action to hinder the growing obesity epidemic in both high income and low income areas.

Diet Quality

The Relationship Between Diet Quality and Socio-Economic Status

People of higher socio-economic status (SES) tend to have better quality diets.

What is a good quality diet? What is a bad quality diet? Why is a bad quality diet detrimental to general health? Link to title: obesity is associated with poor diet quality and therefore low SES (or poverty).

[Figure: a food pyramid detailing what a good quality diet should consist of and in what quantities.]

Extra points: 1) Variables to consider – country, ethnic origin, type of SES indicator; and age, sex, occupation, education, income levels. 2) The difference between poverty and low SES? Poverty is more intense…

Evidence for Socio-Economic Status Affecting Diet Quality

Components of the diet: whole grains/refined cereals, fruit and vegetables, milk, lean meat and fish/fatty meat, added fats, sugars, sweetened beverages, fibre and micronutrients (vitamins and minerals), macronutrients (protein, carbohydrate, sucrose, types of fat).

Data selected from studies focussing on one dietary component in high/low income families to compare diet quality to SES.

Causation of Poor Diet Quality in People of Low Socio-Economic Status

Food prices and diet costs, food access and the food environment, education and culture.

Link to energy density and energy cost: in general, low SES causes people to select food of low cost, and these foods tend to be energy dense.

Helen Golz 18:37, 25 October 2011 (UTC)

Dietary Energy Density

Influence on energy intakes

Energy dense foods have been shown to result in higher energy intakes overall. It has been found that upon eating any given meal under laboratory conditions, participants consume a constant volume. Therefore, the calorie intake is determined by the energy density of the food eaten. In addition to this, palatable, energy dense foods have also been linked to an attenuation of satiety and ‘passive consumption’, thus resulting in a greater energy intake . Foods with a low energy density, however, give a lasting feeling of satiety and fullness. This effect results in a lower consumption of energy during the meal, and for the rest of that day . Previous literature has postulated that the effect of energy density of foods on energy intake is due to poor human ability to distinguish between high and low energy dense foods. Therefore we do not accommodate for this in our eating habits, thus fail to maintain energy balance .

Function of water content

The energy density of foods (MJ/kg) is determined by their water content, whereby energy dilute foods are well hydrated, and energy dense foods are comparably dry. Energy dense foods may also contain fat, sugar and starch, and include foodstuffs such a s crisps, with an energy density of 23MJ/kg and chocolate (22MJ/kg). Examples of foods with a low energy density are fruits and vegetables .

Palatability of energy dense foods

Energy-dense foods tend to be more palatable and pleasurable to eat than foods with a low energy density. Animal studies have shown that sugar and fat stimulate reward centres in brain, resulting in taste preference. It has been proposed that humans, and other animals, developed a taste preference for energy dense foods in order to promote their survival in an environment where food can be scarce and unreliable. Conversely, it has also been suggested that human taste preference for energy dense foods is acquired during early life from their environment. This preference can be developed through repeated exposure, an association with the metabolic consequences, or parental influence.

Hannah Harman 09:43, 27 October 2011 (UTC)

Energy Costs

The Relationship Between Energy Density and Energy Cost

It is seen that there is an apparent inverse relationship between the energy density of foods and the energy cost of food (Drewnowski and Darmon 2005). This meaning that energy dense foods are cheaper for food consumption than the healthier less energy dense food substances (Drewnowski, Darmon et al. 2004). It is noted that the use of refined grains, adding fats and sugars to foods are some of the lowest-cost methods of obtaining energy from our diet (Drewnowski and Darmon 2005). Due to this inverse relationship it is now thought as a way to save money but still have the ability to satisfy the need for food. According to Drewnowski, Darmon et al. it was investigated that the cost of foods such as oil, sugar, potatoes and beans were significantly cheaper than for foods such as meat, fish and vegetables for the equivocal overall energy. Figure 1 shows that when applied to a logarithmic scale the difference in energy cost between fresh produce and fats saw a 1000% variation (Drewnowski, Darmon et al. 2004)

A French study published in 2004 revealed that for every supplementary 100g portion of fruit and vegetable there was an increase in dietary cost within the range of 0.18 – 0.29 Euros per day. The opposite was seen when an additional 100g of fats or sweets were consumed and an observed 0.05 – 0.40 Euro per day reduction in expenditure was the result (Drewnowski, Darmon et al. 2004).

With the above data being taken from France where the obesity percentage for the population is 9.4%, you can’t help but think the effects of this relationship between energy density and energy cost when put into the context of the UK and USA where obesity percentages are 23% and 30.6% respectively.

Furthermore, recent research is now thinking that the obesity epidemic in America is now an economic issue, rather than a medical, education or genetic issue. This can be attributed to reasons such as the ‘falling value of the minimum wage’ and an ever present, especially in the populations that categorise into the lower SES’s, a lack of health and family benefits (Drewnowski and Darmon 2005).

Will edit references at a later date. Ross McEwan 18:55, 1 November 2011 (UTC)

Pricing of Foods and Influence of Income/SES

It is well known that fats and sugars at a very low cost provide dietary energy. Therefore price reduction studies were carried out on alternative foods to investigate whether a reduction in price would see an increase in the consumption of foods such as lower fat foods and fresh fruits. The results show that when price reduction of 10%, 25% and 50% were applied to lower fat foods this resulted in an increase in sale of 9%, 39% and 93% respectively. A second study carried out by the same group, showed that by reducing the price of fresh fruit and baby carrots by 50% led to a four-fold and two-fold increase in the sale of the products respectively (French 2003).

A variation of the above study where an increase on high sugar/fat foods price caused a reduction in consumption of such foods. A 20% increase in the price of soda was associated with a 25% decrease in visits to a fast food restaurant per week (Gordon-Larsen, Guilkey et al. 2011). This can then be further enhanced into a larger context and if taxes were applied to such foods would we see any significant change in BMI or obesity prevalence across the population ((Powell and Chaloupka 2009). We may see a reduction in the consumption but does this directly relate to a decrease in weight (Schroeter, Lusk et al. 2008)? Or would this intervention be considered insignificant? (Gordon-Larsen, Guilkey et al. 2011).Thus, is this observed choice to eat unhealthily that is seen in the lower socioeconomic groups of the population due to economic constraints(Darmon, Ferguson et al. 2002)? Darmon et al highlighted that when cost restrictions were imposed on individuals not belonging to the lower SES groups a reduced intake of fruits and vegetables, lean meat etc and an increase in consumption of cereals, fats and sweets was observed. This, being the pattern seen in communities of the lower SES (Darmon, Ferguson et al. 2002).

Will edit references at a later date. Ross McEwan 18:57, 1 November 2011 (UTC)

Discussion

discussion about general trends regarding relationship between poverty and obesity. Future initiatives and solutions etc. conclusion of article.??

notes/draft so far:

For the most part limited economic resources may shift dietary choices towards an energy-dense, highly palatable diet that involves a high amount of calories per the least volume and ultimately, the least cost. These diets are most likely to contain added sugars and vegetable fats and those from a low socioeconomic status are the most at risk. In addition poverty has been linked to lower physical activity, lack of nutritional education, poorer access to healthcare, greater exposure to marketing of unhealthy foods, and high stress levels .The appropriate built environment allows the individual adequate access to gyms, parks and healthy food options as opposed to an area with an abundance of fast food restaurants and limited recreational facilities. In many cases, poorer areas are most closely situated to clusters of fast food eateries where there is a lack of healthy choices and often in unsafe neighbourhoods there is a tendency to avoid outdoor activity. Studies also suggest that those living in high poverty areas are more likely to watch TV.

Overall, research linking poverty and obesity is more consistent for women and children than men of low socioeconomic status but the research has shown varying results in regards to ethnicity and general trends over the last few decades. The CDC in the US highlight that obesity is higher in minority groups (with the exception of Asian-Americans). In non-hispanic white women, obesity was found to increase as income decreased whereas in non-hispanic black and Mexican-American men obesity decreased as income increased. Although the prevalence of obesity among women with income below the poverty level is higher than among those with higher incomes, most obese women do not have incomes below the poverty level. General obesity trends have shown that between 1986-2002, BMI was increasingly higher in low income groups than high income groups and recently a persons salary was found to be inversely related to BMI and obesity. However in one national study spanning 30 years, the relationship between poverty and obesity weakened among most gender and ethnic groups and especially among women, even though overall obesity prevalence increased considerably. Additionally in some studies obesity rates were found to increase over all income groups and for instance between 1992 and 2008, obesity prevalence increased by 42.3 percent for the lower income group compared to 88.5 percent for the higher income group. This may suggest that the gaps between low and high income groups may be closing over time as more of the higher income population become obese. Yet some may argue that being poor gives you a very unfair disadvantage. Drewonski