Effect of Environmental Factors During Pregnancy

The first 9 months of life are an essential period for the development of the body and for epigenetic changes to take place. The idea that the womb environment impacted on foetal programming began to be explored in the 1980s by David Barker, and this therefore became known as the ‘Barker Hypothesis’. He suggested that the prenatal environment is used as a sort of prediction of the environment in which the child will grow up, and therefore is used to prepare them for these sort of conditions.

Epigenetic modifications are ways in which gene expression is altered, without changes to the genetic code itself. DNA methylation (the addition of a methyl group at a specific point), microRNA expression, imprinting and histone modification are all ways in which the environment can actually alter our gene expression, and therefore impact on our lives. There are many ethical considerations that must be taken into account when studying these early stages of human life, so in many areas the research is limited and there is still probably much more to be discovered. This article will look at some factors involved with pregnancy that can influence the life of an infant.

Maternal Nutrition:

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During the Dutch Hunger Winter in the Second World War, people received less than 30% of the normal calorie intake, due to a Nazi blockade of the Netherlands. Records of pregnant mothers, who suffered in this time, and their children, have been analysed and provide a unique study of the effects of starvation on developing infants. The records show that mothers who were in the first stages of pregnancy during the Dutch Hunger Winter gave birth to normal weight babies, but who had higher than average obesity rates and risk of mental health problems later in life. This fits with the ‘Barker Hypotheses’ as these children were prepared for a life in which food was scarce, although in reality this was not the case. Mothers who were in the later stages of pregnancy gave birth to smaller babies, who had lower than average obesity rates in later life. This could possibly suggest that a large amount of developmental programming concerning metabolism may already have been done by this stage. Effects of this period of starvation could also be observed in the grand children of these women, meaning that these changes appear to be heritable.
Studies of mice have found similar results, and have shown these changes to be due to DNA modifications, such as changes to the pattern of DNA methylation, not due to other factors such as the womb environment alone.
This evidence therefore suggests that the event of starvation of a pregnant mother can have effects on the infant, such as metabolic changes throughout their lifetime.

Nutrition around the time of conception
In rural Gambia, where people’s diet relies mainly on subsistence farming, there are fluctuations in food availability throughout the year. The area has a rainy and dry season each year, so the time of conception can easily be used to predict a typical diet of each woman at this point. In studying this region, researchers found that the maternal diet around the time of conception was linked to the level of DNA mehtylation of specific genes of the infants. This occurs because nutrients from the diet are required as a source of methyl groups, and also for the reactions by which methylation takes place. This means that the mother’s intake of nutrients, such as certain minerals and B-vitamins, can affect the genetic modifications taking place in her child.

Carbohydrate intake
Several studies have found low carbohydrate intake in mothers to be associated with epigenetic changes in infants. For example, Drake et al studied the impacts of a maternal diet lower in carbohydrate and higher in red meat, on the children involved. This study found that the diets lower in carbohydrate and higher in meat, correlated with a greater methylation of a specific DNA site and also higher BMI and waist circumference when the infants reached adulthood.

High calorie intake
A 2006 PubMed study by Villamor and Cnattingius found that a mother gaining weight between pregnancies increased the risk of the child becoming overweight, compared to their siblings. A study of macaques also found overnutrition of a mother during pregnancy to be associated with fatty liver disease and an average of double the percentage body fat of the infant. Several studies of rats have also found maternal overnutrition to be linked to increased appetite, high blood pressure, insulin resistance and increased body fat in offspring. It is thought that the appetite control differences in the offspring may be due to developmental programming changes that effect the concentrations of the hormones leptin and insulin.

Gestational Diabetes
There are many possible effects that gestational diabetes can have on the foetus, such as causing low blood sugar and mineral levels, jaundice and high birth weight. It can, however, also have effects on the child throughout its life, such as increased risk of obesity and developing type 2 diabetes. It is also possible that if gestational diabetes is poorly treated, that the mother’s body may start to break down fat and muscle tissue, rather than using glucose for energy. This causes ketones to be produced and there have been associations found suggesting these compounds are linked with learning disabilities throughout the child’s life.

Maternal Stress:

Studies have found prenatal stress to be linked with hyperactivity, inattention, emotional problems, lower levels of mental development and depression in the children. A study at Imperial College London found that higher levels of cortisol in the mother’s blood caused cortisol levels in the amniotic fluid to be higher. Environmental differences such as this, appear to cause changes to the developing brain of the foetus. These changes may even be structural differences, such as the smaller than average head circumference.
There is also evidence of epigenetic changes created due to the maternal stress. For example, the mother’s stress appears to effect the DNA methylation pattern in several of the infants cells, such as those related to sugar metabolism and T cells of the immune system. Although the impacts of this are largely unknown, it suggests that the children may be at a greater risk of diabetes, obesity and asthma.
Maternal stress also seems to be linked to increased methylation of the glucocorticoid receptor gene (NR3C1). This reduces its expression and means that a smaller amount of the receptor protein is produced. This is a receptor for cortisol in the infant’s brain, and is involved in a feedback mechanism which, in a healthy child, would reduce the amount of cortisol released. This can result in a greater stress-response in the child, and can increase the risk of depression.
A significant study in this area of research is that of children born following an ice storm in Canada, throughout which their pregnant mothers had been under intense stress. The 89 children involved were studied at 5 years old, and this study, published in 2008 found that higher stress levels of the mothers during pregnancy were associated with lower IQ, verbal IQ and language ability in the children. These children will continue to be studied to find out how they are affected later in life.

Alcohol Consumption:

The fact that alcohol consumption during pregnancy affects development is well known. This has been documented by many studies and a wide range of negative impacts have been found. For example, a 2012 study of prenatal alcohol exposure found that higher levels were associated with lower levels of attention and longer reaction time in 7 and 8 year old children. A previous study published in 2001 found a statistically significant association between alcohol exposure and reduction in the size of the frontal cortex. This area of the brain is involved with higher mental processes, such as thinking, decision making and planning, so underdevelopment can easily be linked to the observed effects of FAS. There are many different mechanisms that could explain how these effects are brought about. For example, greater oxidative stress, damage to mitochondria or glia cells, changes to growth factor activity and chemical messaging systems or altered gene regulation could all potentially cause cells to die. It is almost certain that multiple mechanisms occur to create FAS. More can be read about this from the National Institute on Alcohol Abuse and Alcoholism.

Maternal Smoking:

Exposing a foetus to tobacco constituents has been shown to be linked to reduced lung growth, infection of the respiratory tract, asthma and negative impacts on psychological development. Many substances, including nicotine and carbon monoxide, are carried in the mother’s blood and transferred to the developing baby via the placenta. Several of those substances can even be found in higher concentrations in the foetus than in the mother, such as nicotine, which can be 15% greater.
It is thought that these substances impact upon the foetus by creating epigenetic changes. For example, a 2010 PubMed study by Suter et al, found that maternal smoking was associated with greater levels of DNA methylation in several areas, affecting gene expression involved in development and growth, as well as possibly causing modifications to the placenta. Maternal smoking has also been found to by Maccani et al, to be associated with reduced amounts of a specific miRNA. MicroRNA are small, non-coding pieces of RNA, which pair up with mRNA, affecting translation of specific proteins. These two mechanisms begin to explain how it is possible for smoking to damage a developing child, however, many other processes may be involved.

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Maternal Infection:

Infection during pregnancy is thought to be linked to a higher risk of neurological disorders, including autism. This effect would depend on the severity of infection of the mother, but it appears that proteins produced by the mother in her immune response may effect the infant’s brain, either directly or by effecting nutrient and oxygen supply via the placenta. This correlation has been found by several studies, for example, Atladottir et al in 2010, who found that hospital admission of a mother due to viral infection in the first trimester was associated with a three times greater risk of autism. When studying the total duration of pregnancy, however, they found no correlation.
For many types of virus, it is also holds true that infection early on in pregnancy presents a greater risk to the foetus. For example infection with rubella in the first 11 weeks of pregnancy is associated with a 90% risk of affecting the foetus, for example causing mental impairment, deafness, inflammation or cataracts. Other infections such as chickenpox or toxoplasmosis in pregnancy can also be extremely dangerous to the foetus.

Overall, it is clear that the time during pregnancy is crucial to a baby’s development, and can have long term consequences, affecting its whole life. There are many factors that can influence it’s development and genetic programming throughout this time, and little detail is known about most of these factors. There are also many more factors that would have an influence on the developing foetus. The more research that is carried out, the more we find out about the complexities of the genome and environment’s interaction. The extent to which conditions during pregnancy can effect a person’s life needs further exploration, and we so far can not know how many of the events of a mother’s life can influence the development of her child.

Sources used:
The Open University
Nature
psychiatry.emory.edu
Science Direct – Prenatal Stress
– Impact of prenatal stress, foetal alcohol exposure, or both on development
PubMed – Project Ice Storm
Frontiers in Genetics – developmental programming
American Psychological Association
The Epigenetics Revolution
The Lancet
American Journal of Obstetrics and Gynecology
National Institute on Alcohol Abuse and Alcoholics
Journal of the American Academy of Pediatrics
Autism Speaks
BioMed Central
US National Library of Medicine

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Allergies on the Increase?

– Each year, in the UK, the number of allergy sufferers increases by 5%
– The incidence of hay fever in children in the UK has tripled in the past 30 years
– Initialy, this trend was only apparent for asthma and hay fever, however, food allergies are also now on the rise
– In the last decade, the number of cases of food allergies has doubled
– Since 1990, there has been a 500% increase in hospital admissions due to food allergies

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Explaining this trend:

Is the rise due to increased awareness, or actually due to the development of allergies becoming more frequent?
It is true that awareness is increasing, and therefore a higher percentage of allergies are becoming diagnosed. However, there is a large amount of evidence suggesting that there is more to it than this. It seems that the incidence of allergy development is actually increasing too. The reason for this has been hotly debated.

A bit of background information:

The development of an allergy is determined by both genetic and environmental factors. The evidence for a genetic component can be clearly observed through the study of twins. A PubMed study published in 2000, found that 7% of fraternal twins shared the same peanut allergy, whereas 64% of identical twins shared this same allergy.
An allergy occurs when the immune system mistakingly identifies a harmless substance, such as a food protein or pollen, as a harmful pathogen, causing an immune response. There are 5 basic types of antibodies, one of which (IgE) is responsible for allergic reactions. Everybody has this antibody type, however, the lymphocyte should be able to distinguish between harmless proteins and those that are dangerous.
So why are allergies becoming more common? We know that this increase can not be due to genetic factors, as the rate of change is far too rapid. This indicates that there are environmental factors to blame. Genes can also be switched off or on as a result of environmental factors. This process, called epigenetics, could have a part to play in allergies. For example, infection by viruses can cause epigenetic changes, which are able to effect the bodies immune response. Several of the possible environmental causes for increasing allergies are discussed below:

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‘Sunshine Hypothesis’
Lifestyle changes mean that children now spend a much higher percentage of their time indoors, reducing their sun exposure. Receiving sunlight is important to our bodies because 80% of our vitamin D is produced in the skin in UV light, and does not come directly from our diet. It is also known that using sunscreen with a protection factor of just 8, decreases the production of vitamin D by 98%. These changes explain why vitamin D deficiency has become far more common. Studies have repeatedly found that the prevalence of allergies is highest in westernised countries. In China, this correlation also holds true for cities that differ in level of westernisation. A possible explanation for this is that people in westernised areas generally spend a greater proportion of their time indoors, and generally have lower levels of vitamin D.
It is also known that vitamin D can have inhibitory effects on some of the T helper cells of the immune system, and therefore could be involved with allergic responses.

Pollution Hypothesis
Air pollution has become a major public health concern in recent decades. This pollution includes carbon dioxide, nitrogen dioxide, CFCs, ozone, sulphur dioxide and particles in suspension. There is strong evidence that pollutants are able to exacerbate existing allergies, such as asthma. For example, it has been shown that ozone immediately worsens dust mite allergies, and causes inflammation of the airways.
What is currently unknown, is whether this air pollution can actually induce the development of new allergies. Research into this has been carried out, for example a 2004 PubMed study by Gauderman et al found that the likelihood of developing asthma was higher in children who exercised in areas with high ozone concentrations. NO2 and exhaust particles have also been found to be associated with asthma development. However, this data is frustratingly inconsistent, as several studies have found no correlations. These different findings are thought to be due to differences in lifestyle factors of the participants, however, the exact reasons are unknown. Despite this uncertainty, possible mechanisms have been suggested to explain how pollution could cause the development of an allergy. For example, it has been shown that diesel exhaust particulates (DEPs) stimulate the epithelial cells of the airways to produce cytokines and chemokines, causing inflammation. This production is due to increases in transcription of the relevant genes. There are many other possible ways that pollution may effect inflammation and antioxidant pathways, meaning that the response to allergens could be affected.
It has also been suggested that climate change could affect allergies, as increasing temperatures change the distribution of allergens and can also alter the allergenic potential of pollen.

Diet Hypothesis
Processed foods are also under suspicion as a potential cause of allergy development. Our diets now contain far more processed foods, and are lacking in fruit and vegetables. It is a possibility that these diet changes have resulted in greater consumption of allergenic substances such as wheat. It is also possible that coming into contact with allergens at an early age could possibly increase the risk of developing an allergy. There has been some research into whether reduced omega-3 or antioxidant intake could be linked with allergy development. In some studies, diets low in oily fish have correlated with increased risk of asthma and allergies, but this evidence is inconsistent.

‘Hygiene Hypothesis’
It is well recognised that there is a correlation between high living standards and high frequency of allergic diseases. This high standard of living involves sanitation technology such as clean water and food supply as well as the use of antibiotics. Our lifestyle changes have resulted in the immune system coming into contact with fewer micro-organisms during childhood.
It is also known that children who have older siblings are less likely to develop allergies, and this likelihood also depends on the number of older siblings that they have. This link between birth order and vulnerability to allergies could be due to the fact that having more siblings around increases the number of germs that the child is exposed to. It is thought that in areas of the world where hygiene standards have greatly improved, the immune system is not fighting against as many pathogens, and this creates an imbalance which means we have a predisposition to the development of allergies. The imbalance that is created involves the quantities of T1 and T2 cells of the immune system. It is thought that people who have not come into contact with as many micro-organisms have fewer of the T1 response cells. T2 dominance is known to be associated with asthma, hay fever and other allergies. Therefore the micro-organisms that we have evolved with, could be essential to the development of our immune system.
The results of several animal studies have also given support to this hypothesis. For example, a German study published in December 2009 in the Journal of Experimental Medicine, found that exposing pregnant mice to barnyard micro-organisms, resulted in their offspring being resistant to allergies. The fact that children growing up on farms also have a reduced likelihood of developing allergies, suggests that this may also apply to humans.
As breast milk contains over 700 varieties of bacteria, I would also suggest that this could potentially have benefits to a baby’s immune system and affect the development of allergies. Therefore the use of formula milk is another factor that could be considered as it would reduce the natural exposure of infants to micro-organisms and therefore tie in with the ‘hygiene hypothesis’. This could then bring up questions about the significance of a mother’s diet during the breast feeding period, and whether this would affect the development of allergies in the infant.

Overall, it appears that there is no certainty as to why the frequency of allergies is increasing in developed countries. There is, however, compelling evidence to suggest that environmental factors associated with our changing lifestyles are causing changes to our immune response. There is a growing body of evidence to support the ‘hygiene hypothesis’, but it is also possible that other factors, such as dietary changes and pollution could be contributing to this apparent trend.

Sources used:
Live Science – food allergies
British Society for immunology
https://www.allergyuk.org
Science Direct – Immunobiology 2007
Fightthecauseofallergy.org
PubMed
Biomed Central
National Geographic
Korean Journal International Medicine
http://www.cdc.gov/

Sustainable Development Goals

On 25 September 2015, these 17 goals were created at the United Nations Summit. These follow on from the 8 Millennium Development Goals that were created in 2000.

First some good news…

Before moving on to the next set of goals, it is important to reflect on some of the huge achievements that have already been made:
– Since 1990, extreme poverty has been halved
– In developing countries, 90% of children now receive primary education, compared to 83% in 2000
– There is now gender equality in primary education
– 17,000 fewer children die each day than in 1990
– Maternal mortality has been reduced by 45% since 1990
– In 2012, 9.7 million people received HIV medication
– Since 1990, 2.3 billion people have gained clean water access
– The MDRI and HIPC initiatives have cancelled $97 billion worth of debt, since 1996, mostly in sub-Saharan African countries.

What next?

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These new goals have been set as targets for 2030. Many of these goals build upon the MDGs, however there are several new issues included. For example, the need to increase environmental sustainability is reflected in many of these goals. This means that developed countries have targets to work towards at home, as well as overseas, such as altering national policies and improving education to tackle climate change. The Pope is in support of this, saying this week, on the topic of climate change, that “that we have a sacred obligation to protect our planet”.
Barack Obama has also given a powerful defence of this new agenda, making the statement that this new agenda is ‘not charity but instead is one of the smartest investments we can make in our own future’.

Meat eaters

Is there a link between meat and cancer? It’s been hotly debated for years, and the findings of different studies is often contradictory. However, several large scale studies have been carried out and much of the evidence has been found repeatedly. The World Health Organisation have found that 30% of cancers in Western countries can be attributed to dietary factors. With more than one quarter of deaths in the UK being due to cancer, this is clearly a crucial area of research.

Which meats to blame?
A 2007 Plosmed study of 500,000 people aged 50-71 found a significant association between red meat consumption and increased risk of esophageal, colorectal, liver and lung cancer risk. The difference in risk for each cancer type, varied between 20% and 60%, between the lowest and highest consuming groups.
The European Prospective Investigation into Cancer and Nutrition (EPIC) followed over 500,000 people in 10 European countries, and was published in 2013. This, however, found no association between fresh meat consumption and cancer risk, but suggests that an increase of 50g per day of processed meat increases a person’s risk of death from all causes by 18%, partly due to cancer.
It has been repeatedly been found that there is no correlation between the consumption of white meats and cancer. For example, a 2002 Pubmed Meta-analysis found no significant association between total meat consumption and colorectal cancer risk. The EPIC study mentioned above, also found that people eating no meat at all were at a higher risk of early death from any cause than those eating a small amount of red meat.
These mixed reviews of meat can be confusing, however, small amounts of fresh meat can be an important source of essential amino acids, iron and vitamins B6 and B12, in a healthy diet. Processed meats, on the other hand, generally get a poor right up, and have been blamed for causing heart disease and cancer. The Department of Health recommends that you eat less than 70g of red or processed meat per day. It is widely accepted that there is no risk of cancer associated with white meat, so the following information only refers to red and processed meats.

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Causal Relationship
There are several suggested mechanisms that have been put forward to possibly explain the relationship between meat and cancer risk. These processes are ways in which meat could actually cause cancer, and a thorough understanding of these could become proof of the relationship.

– A 2014 study in the journal ‘Proceedings of the National Academy of sciences’ suggested that the link between red meat and cancer may be due to Neu5Gc (N-glycolylneuraminic acid). Red meat contains high concentrations of bioavailable Neu5Gc. This molecule can act as a foreign antigen, and cause systematic inflammation when in contact with antibodies, therefore increasing cancer risk. The findings were that exactly this did happen in mice, and the risk of cancer was increased 5 times by long exposure.

– A 2012 study published in ScienceDirect, drew attention to the heterocyclic amines (HCAs) that are present in red meat that has been heated to high temperatures. These are formed when molecules in the meat, such as amino acids and sugars, react at high temperatures. These compounds are carcinogenic, and the study did find associations between the intake of specific HCAs and risk of breast and lung cancer.

– Polycyclic aromatic hydrocarbons are also formed in flames, and attach to the surface of the meat when it is cooked over an open fire or smoked. These compounds are also known to be carcinogens.

– Red and processed meat also contains haem, which could damage cells of the bowel, causing them to divide at a greater rate, and therefore increasing the potential for cancer to occur. Alternatively the haem may stimulate the production of N-nitroso compounds in the gut. A 2003 Pubmed study supports this hypothesis, as it found that haem supplements increased the concentration of the carcinogenic N-nitroso compounds in human faeces.

The Role of Equality in Health and Happiness

It is an interesting observation that there is almost no correlation between GNP per capita and life expectancy, amongst developed countries. Within a society, however, we know that personal wealth does play a large role in determining life expectancy. The difference between these two measures is that within a society, GNP per capita is a measure of relative wealth, and is therefore a comparison with others. By using the difference in wealth of the top 20% and bottom 20%, Richard Wilkinson has drawn attention to the strong positive correlation between income inequality and health and social problems. This is shown on the graph below.

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This does not simply point out that poverty causes poor health and unhappiness. The evidence actually goes beyond the evidence and suggests that inequality actually leads to worse health outcomes and happiness for the most affluent in society as well as those in relative poverty.

It is thought that higher income inequality causes greater feelings of status insecurity due to comparisons against others in society. The fear of this judgement and a lack of social cohesion increases stress and therefore cortisol levels. This results in increased health and social problems.

Evidence from several studies supports this link between inequality and poor health. For example in the USA in 2001, Lochner et. al found that individuals living in states with greater inequality were at a 12% higher risk of death. In 2009 a study published in the British Medical Journal produced some shocking statistics about the impact that inequality is having on people’s lives in the USA. This study concluded that almost 884,000 deaths per year could be attributed to high inequality, and that this number would be prevented if the Gini coefficient value could be reduced to 0.3 (the average for OECD countries), from its value of 0.357. This is one third of deaths in the USA!

Supporting this, a 2009 BMJ meta-analysis by Kondo et al, found an 8% higher mortality risk per 0.05 increase in the Gini coefficient value.

There is also evidence to suggest that income inequality correlates with lower happiness in societies. For example, a 2011 study carried out in the university of Virginia found that from 1972 to 2008, people in America were happiest in years when income inequality was lower.

The 2015 World Happiness Report found that three quarters of differences in happiness between all countries is due to 6 factors: GDP per capita, healthy years of life expectancy, social support, trust, freedom and generosity (measured in donations comparative to income). Although this does not specifically highlight income inequality as a factor in happiness, it has been found to be linked to several of these 6 factors. For example, Richard Wilkinson’s research has also found a strong negative correlation between levels of trust in society and income inequality. There is also a strong correlation between income inequality and social immobility which would therefore mean that there was less freedom in more unequal societies. It is also likely that social support may be reduced by inequality as isolation tends to be higher.

The following maps show happiness rankings, and the Gini Coefficient (a measure of income inequality). It can be seen that there is some correlation, especially when considering the worlds happiest countries: Switzerland, Iceland, Denmark, Norway, Canada, Finland, Netherlands, Sweden, which all have fairly low Gini Coefficient values.

Happiness:

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-from the Washington Post

Gini Coefficient: (higher being less equal)

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-from the Business Insider using World Bank Data

The 2015 World Happiness Report states that ‘happiness is increasingly considered a proper measure of social progress and a goal of public policy’, and there are several organisations, such as Action for Happiness, who encourage people to see the importance of happiness, rather than focusing on financial and status goals.

There is also a large amount of research to suggest that happiness results in a healthier life. For example, Kubzansky’s 2007 paper found that enthusiasm, hopefulness, engagement in life, and emotional balance correlated to a lower risk of coronary heart disease. This is only the tip of the ice burg when it comes to how happiness can be beneficial to your health. It has been suggested that being happy can also reduce the risk of type 2 diabetes, high blood pressure and infection.

Despite happiness having recently gathered interest and making several headlines, there is still a lack of research. An Online Library search reveals around 400,000 results for the word ‘depression’, compared with only 50,000 for ‘happiness’. Now that’s depressing!

Sources used:
inequality.org
TED
PubMed
WHO – obesity and inequalities
BMJ – income inequality, mortality and self rated health
Psychology today
Harvard School of Public Health

How will we feed the growing population?

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The population of the world is expected to exceed 9 billion by 2050. Most of this growth will occur in developing countries, so increased wealth and urbanisation will also contribute to increasing demand for food. It is estimated that, by 2050, food production must increase by 70%. This will require policy changes, the support of agriculture, and increased investment by developing countries, or greater donations from elsewhere. It is also estimated that 80% of the increased production in developing countries must come from increased yield, not expanding the amount of farm land.
This brings up several problems. For example, the rate of growth of yields has been declining for several years, and climate change may reduce Africa’s agricultural yields by up to 30% by 2100. An increasing amount of land is also being used for biofuel production. Currently less than 3% of crop growing land is used to produce biofuels, however, could increasing fossil fuel prices change this?

So it is clear that in order to feed the growing population we can not continue as we are. Here are several possible options that could help to increase food production in the future:

Genetic Modification of Rice
In India and Bangladesh alone, 4 million tonnes of rice (enough to feed 30 million people) is destroyed by flooding each year. Most strains of rice will die if they are submerged within 3 days, however, through genetic engineering, a variety that can survive submergence for 2 weeks has been developed. This tolerance is brought about by the overexperssion of the Sub1A gene. Rice crops have also been modified to increase their resistance to herbicides, making it easier to control competing weeds.
In 2013 this flood resistant rice was received by more than 4 million farmers.

Biofortification
Biofortification is the process of breeding food crops with a higher micronutrient content. This technique is mainly used to prevent deficiencies in poor rural communities, without large changes to people’s diets. For example, orange-fleshed sweet potato has been the first biofortified crop to be widely consumed. In many African countries people’s diets are high in the staple foods maize, cassava and sweet potato, but lack diversity. It is estimated that in Africa 32% of children under 5 years old are deficient in vitamin A. The orange-fleshed sweet potato was biofortified with vitamin A, and provided in Mozambique and Uganda by the research organisation HarvestPlus.
HarvestPlus is working on the biofortification of beans, cassava, maize, pearl millet, rice, sweet potato and wheat, to include vitamin A, zinc and iron.

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Eradication of Diseases
Pathogens cause huge losses in both crop and livestock yields. Surveillance, diagnosis and vaccines can all be used to reduce these losses. For example, the rinderpest virus that used once infected livestock, has been eradicated. This virus killed up to 95% of those infected, dramatically reducing meat and milk yields. According to The Department of International Development, it had been a problem for over 10,000 years, but the last known case was in 2001 in Kenya. Live vaccines were initially used over 100 years ago, when serum was taken from recovered animals, combined with blood from infected animals and found to provide long term immunity. After this, vaccines were created that produced fewer symptoms, were heat stable and could be produced in large quantities.
Rinderpest and smallpox are the only two infectious diseases to have been eradicated, but in the future, further eradications may allow greater increases in yield.

The Pig Idea
The Pig Idea is a campaign encouraging the use of food waste to feed pigs. One third of all food is wasted globally, and currently there is a ban in the EU on feeding this waste to pigs. However pigs are instead fed on wheat, maize and soy, which is suitable for humans to eat and is grown on land created by the deforestation of the Amazon rainforest. The increasing price of these crops has already put many pig farmers out of business. It is also estimated that around 20 times less carbon dioxide would be emitted by feeding food waste to pigs, rather than allowing it’s decomposition.
However, some countries have already accepted this idea. For example, the Japanese government supports pig farmers that feed their animals waste, and this meat is sold more cheaply in supermarkets.

Growth of Acacia trees in Africa
These trees grow in virtually all environments, from deserts to the fringes of tropical rain forests. This is due to their ability to fix nitrogen from the air and extract water and nutrients from deep in the soil. Many of these trees have been removed to create land for farming.
However, land degradation is a huge problem in areas of Africa, and acacia trees improve structure and fertility in the soil, as well as preventing water runoff that caused erosion, and loss of nutrients. They can provide shade for plants and animals, and can produce pods for animal fodder and many goods.

Sweeteners and Low-Fat Foods – Good or Bad?

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Sugar or Sweeteners?

On average people in Britain consume 22 teaspoons of sugar per week. Sugar has been proven to be addictive as it causes a release of dopamine in the brain. Sugar also causes an increase in cholesterol and therefore raise the risk of heart disease, as well as increasing the risk of type 2 diabetes, tooth decay, obesity and possibly cancer.

Sugar substitutes are added to many foods for their sweet taste and because they contain fewer calories than sugar. This sounds like a great way to slow the growth of many health conditions that are associated with our diets. However there have been many studies into the effects of these sweeteners, and the low fat foods that they are often added to, have on our health.

Claims have been made about sweeteners causing cancer, strokes, seizures, low birthweight, high blood pressure, vomiting, dizziness and the list doesn’t stop there. However, none of this has been proven by medical trials so the use of sweeteners in Europe continues to increase.

Aspartame is probably the best known artificial sweetener and it is commonly used as it is 200 times sweeter than sugar and low in calories. However, it has been claimed to be associated with many health problems. However, when consumed, hardly any aspartame enters the blood because when it is broken down into different products that are then absorbed. Does this mean that aspartame is off the hook?

Artificial sweeteners have been linked to changes gut bacteria, resulting in a higher blood sugar level, and therefore a higher risk of type 2 diabetes when the liver does not respond to insulin. For example, one study showed that mice fed on sweeteners broke down more carbohydrate from their diet than normal, which would therefore increase their blood sugar. A study in humans also found that long term sweetener consumption was associated with a change in gut bacteria, and an increase in waist circumference and blood sugar levels.

Are Low-Fat Foods the Healthier Option?

Low-fat foods may sound like a way to cut calories and improve health, however, the lack of fat is usually compensated for by added sugar. There has recently been a large amount of debate about whether sugar could be more damaging than fat, which had previously been blamed for the increase in many health conditions. For example it is now being suggested that sugar may cause a larger increase in cholesterol than fats, leading to an increased risk if heart disease.

There could also be psychological effects cause by these foods. It has been suggested that eating low fat foods could cause cravings at a later time for fats as the body has not received the fats that it expects. I would suggest that it might be possible for sweeteners to have the same effect, maybe causing sugar cravings, and stimulating our appetite? Could it also be possible that even the packaging of the food could have a psychological effect?

However there is also increasing research showing the importance of fat in our diets. For example vitamins A, D, E and K are fat soluble and therefore fats are required to transport these around the body. Saturated fat in the diet is also necessary for calcium absorption, and has been shown to help the body reduce levels of low-density lipoprotein (a risk factor of heart disease). Saturated fat is also known to be essential to the functioning of the brain, nervous and immune systems, liver and lungs.

Although fat has consistently been seen as the cause of rising obesity levels, it is also known that eating fat results in the production of a hormone called Leptin which causes us to feel satisfied after eating, as it affects thyroid function, and therefore the ability to burn fat and your energy levels.

Further to this, a recent study (September 2014) at Lund University in Sweden found that eating full fat dairy was linked with a 23% lower risk of developing type 2 diabetes. It was also found that fatty meat was associated with less risk than lean meat.

Therefore it seems that our opinion of fats and sugars is rapidly changing, and we remain unsure of the extent to which sweeteners can cause damage, compared to sugar.