Significant changes in the earth’s climate
system which result in new weather patterns that may last tens to millions of
years is referred to as Climate Change. The climate system
receives energy from the sun as well as dissipates energy to the outer space in
order to maintain the balance of incoming and outgoing energy. This balance of
incoming and outgoing energy, and the passage of the energy through the climate
system, determines earth’s energy budget. When the incoming energy is greater
than the outgoing energy, earth’s energy budget is positive and the climate
system is warming. On the other hand, if
more energy goes out of the climate system compared to that which comes in,
then the energy budget becomes deficit or negative and earth experiences a
cooling effect.
The climate system is made up of five
interacting parts which include:
- Atmosphere
(air)
- Hydrosphere
(water)
- Cryosphere
(ice and permafrost)
- Biosphere
(living things)
- Lithosphere
(earth’s crust and upper mantle)
Climate change is widely recognized as one of
the most urgent problems currently facing humanity, and the world at large.
Fortunately, humans have the knowledge, technologies, and resources to solve
this problem, in ways that support the most vulnerable nations and communities.
We must take care of the earth’s atmosphere which is part of a global system
that keeps the temperature of the universe within a habitable range. Sadly, we
have not kept up with this mandate due to industrialization.
Since the advent of the industrial revolution,
humans and their activities have continued to alter the composition of the
atmosphere by burning fossil fuels such as coal, oil and gas. The resulting
carbon dioxide (CO2) builds up in the atmosphere, creating the greenhouse
effect. The greenhouse effect then traps energy from the sun and raises the
temperature of the earth causing a positive change in the climate. An example
of greenhouse gases is methane released mainly by natural gas production and
nitrous oxide from nitrogen-based fertilizers. Greenhouse gases occur naturally
and are essential to the survival of living things because they keep some of
the sun’s warmth from reflecting back into space making the earth habitable. However,
human activities including industrialization, deforestation and large scale
agriculture, have increased the quantities of these atmospheric greenhouse
gases to record levels not seen in three million years and which threaten the
existence of life. As populations, economies and standards of living grow the
cumulative level of greenhouse gas emissions increases.
Currently, the wide-ranging impacts of
climate change are felt globally: various studies have reported an increase in
annual temperature worldwide which is predicted to further increase by the year
2050. The ecosystem is changing and if nothing is done, many species may go
extinct because their habitats are changing faster than they can adapt.
We can choose a future that prevents the
worst impacts of climate change, by controlling our population as well as making
a rapid transition from fossil to renewable energy sources which is very
affordable.
Global
warming is the continuing rise in the average temperature of the Earth’s
climate system. It is a consequence of climate change and is reflected by
temperature measurements and its numerous resulting effects. Global warming has
been happening for a long time, however, increased intensity of its effects was
observed in the 1900s. Therefore, the term is used mainly to describe the
observed and ongoing increase in average air and ocean temperatures since 1900
caused predominantly by the emissions of greenhouse gases (GHGs) in the modern
industrial economy. Although global warming and climate change are sometimes
used interchangeably, they are not exactly the same. Global warming is a result
of climate change, it is one of the many effect of changes in the climate
system. On the other hand, climate change is much broader and encompasses both
global warming and its effects including changes to precipitation and other
environmental impacts that differ by geographic region. The effects and impacts
of global warming are broad and include the following
- Rising sea levels
- Regional changes in precipitation
- Frequent extreme weather events such
as heat waves and wild fires
- Expansion of deserts
- Destruction of infrastructure and food
insecurity
- Water pollution
- Reduced water quality
- Extinction of some ecosystems and
species
As
the climate becomes warmer, the nature of global rainfall, evaporation, snow,
stream flow and other factors that affect water supply and quality change. Surface
temperature increases are highest in the Arctic, with the continuous retreat of
glaciers, permafrost, and sea ice. Generally, increase in temperature results in
more rain and snowfall for some regions while it causes droughts and wildfires
in other regions.
Resulting effects of
global warming such as increased variability in weather patterns, heat waves,
heavy precipitation events, flooding, droughts, intense storms, sea level rise,
and air pollution negatively affect public and global health. The specific
health effects vary across geographic regions, age, economic resources and
populations. More so, global warming may intensify already existing health problems
in addition to causing new health issues.
In general, extreme
heat events remain a cause of preventable disease and death worldwide. Public
health is affected by disruptions of physical, biological, and ecological
systems. The health effects of these disruptions may include increased
respiratory, kidney and cardiovascular disease, injuries and premature deaths
related to extreme weather events such as heat waves and heat stroke, changes
in the prevalence and geographical distribution of food- and water-borne
illnesses and other infectious diseases, and threats to mental health.
A balanced diet is a
healthy diet that contains all the necessary food nutrients in their right
proportions or recommended quantities. Eating a healthy diet daily and throughout
one’s life helps prevent different forms of malnutrition as well as a wide range
of non-communicable diseases (NCDs) and conditions. The exact composition of a
balanced and healthy diet varies based on specific individual characteristics such
as age, gender, lifestyle, level of physical activity, cultural context,
locally available foods and dietary customs; however, the basic principles of
what constitutes a healthy diet remain the same. Basically, a balanced diet
includes the six classes of food: carbohydrates, protein, fats and oil, fruits
and vegetables, minerals, vitamins and water.
The
benefits of a balanced diet are broad and far reaching. Eating a healthy,
balanced diet is one of the most important things that protect health. In fact,
up to 80% of premature heart disease and stroke can be prevented through
healthy diet and physically activity. A healthy diet helps lower the risk of
heart disease and stroke by:
- Improving cholesterol levels
- Reducing blood pressure
- Maintaining body weight
- Controlling blood sugar
- Helping the body function properly
For infants and young
children, a balanced diet provides optimal nutrition which fosters healthy
growth and improves cognitive development especially in the first two years of
life. It also reduces the risk of becoming overweight or obese and developing NCDs
later in life. For adults, eating a balanced diet which contains most or all of
the classes of food is essential to remaining healthy. Specifically, eating at
least 400g or five portions of fruits and vegetables daily reduces the risk of
NCDs and helps to ensure an adequate daily intake of dietary fiber.
Additionally, reducing the amount of total fat intake helps to prevent
unhealthy weight gain in the adult population while limiting salt intake to the
recommended level of less than 5g per day could prevent up to 1.7 million
deaths annually. More so, minimizing the intake of free sugars in both adults
and children also provide additional health benefits by preventing dental
caries (tooth decay), cardiovascular diseases and obesity.
Despite the benefits
and established guidelines of healthy eating as well as the negative health
effects associated with not eating balanced diets, many people still consume foods
high in energy, fats, free sugars and sodium. This is as a result of increased production
and availability of processed foods, rapid urbanization and changing lifestyles
which have resulted in a shift in dietary patterns. People no longer eat enough
foods beneficial to health including fruits, vegetables and other dietary fiber
such as whole grains.
Diet is influenced by
personal, social and economic factors that interact in a complex fashion. These
factors include income, cost, availability, palatability, individual
preferences, personal beliefs, culture and geographical aspects including
climate change. As a consequence, promoting a healthy and balanced diet or food
environment requires multiple sectors and stakeholders, including government, private
sectors and the public in general.
Nutrition can be
defined as the science that interprets the interaction of nutrients and other
substances in food as well as their relationship to the maintenance, growth,
reproduction, health and disease in an organism. It encompasses various stages
of food intake including absorption, assimilation, biosynthesis, catabolism and
excretion. The major sources of nutrients include foods, drinks, fruits,
vegetables and multivitamin capsules. To ensure the preservation and retention of
nutrients, foods must be prepared and stored using methods that prevent
nutrients from oxidation, and that reduces risk of foodborne illnesses.
The lack of nutrients
in humans is called under-nutrition or malnutrition and may result in
deficiency-related diseases such as blindness, anemia, scurvy, preterm birth,
stillbirth and cretinism. On the other hand, having some nutrients in excess
may cause health-threatening conditions such as obesity, metabolic syndrome and
chronic systemic diseases such as cardiovascular disease, diabetes and
osteoporosis.
The importance of good
nutrition is obvious and cannot be overemphasized. The association between good
nutrition and healthy weight, reduced chronic disease risk, and overall health
is also too important to be ignored. Good nutrition is a vital part of a
healthy lifestyle and food choices affect mood and health. In combination with
physical activity, good nutrition helps in the maintenance of a healthy weight,
decreases the risk of chronic diseases such as heart disease and cancer and
promotes overall health. One of the major impacts of poor nutrition is obesity;
for example, about one-third of adults (33.8%) in the United States are obese
and approximately 17%- about 12.5 million children and adolescents between the
ages of 2 to 9 years are also obese. Irrespective of one’s body mass index, poor
nutrition is associated with major health risks that can lead to morbidity or
mortality. Some associated diseases include heart disease, hypertension (high
blood pressure), type 2 diabetes, osteoporosis, and certain types of cancer.
The great news is,
these health problems and diseases are mostly preventable by making wise food
choices. It remains important to instill healthy eating habits in children who
more often than not carry these habits into adulthood- teaching children how to
eat healthy at a young age will more likely help them stay healthy throughout
their life. Conclusively, eating healthy balanced diets, which is the only
source of good nutrition gives the body the nutrients it needs to stay healthy,
active, and strong.