DIET,
OBESITY AND METABOLIC DISEASE
INTRODUCTION
Obesity has emerged as a
pervasive public health problem in the last decade. The disorder manifests as
the abnormal or excessive fat accumulation in adipocytes after an excessive
calorie ingestion through consumption of food that exceeds the body’s metabolic
necessities for growth and development and may impair the health of the
individual. The overweight and obesity can be diagnosed by checking the Body
mass index (BMI), which is a simple index of weight-for-height. It is defined
as a person’s weight in kilograms divided by the square of his height in meters
(kg/m2) (WHO, 2016). A person with BMI greater than or equal to 25
is inferred to be overweight and one with a BMI greater than or equal to 30 is
classified to be obese. The fundamental reason for this is the imbalance
between calorie intake and calorie expended by an individual. WHO database show
that, the prevalence of obesity globally was about 13% of the world’s adult
population (11% of men and 15% of women) in 2016 and that of metabolic syndrome
(MS) is estimated to be between 20-25% and is associated with a two-fold
increase in the risk of coronary heart disease, cerebrovascular disease, and a
1.5-fold increase in the risk of all-cause mortality. The
frequency of obesity got nearly triple folded since 1975, arguably making it
the most serious global epidemic. In 2016, more than 1.9 billion adults, who
were 18 years and older and 41 million children under the age of 5 were
overweight or obese (WHO, 2016). Globalization has deeply affected people and
the way they live and eat. It has brought forth a need and urge to consume high
calorie diets from fast food chains. Researches that were conducted on the
possible outcomes and health hazards which includes obesity and other metabolic
disorders, has proved that it is time to start limiting the intake and focus
more on an everyday healthy diet. The prevalence of the metabolic syndrome and
cardiovascular disease is expected to rise along with the global obesity
epidemic, therefore a greater emphasis should be given to effective early
weight-management to reduce risk in pre-symptomatic individuals with large
waists (Thang S Han, 2016).
OBESITY,
CARDIOVASCULAR DISEASES AND METABOLIC SYNDROME
A person can be diagnosed if he
has metabolic syndrome if any 3 among increased waist circumference (?102 cm in
men and ? 88 cm in women elevated triglycerides (?150 mg/dl), reduced HDL
cholesterol (<40 mg/dl in men and < 50 mg/dl in women), elevated blood
pressure (?130/85 mm Hg or on treatment for hypertension), or elevated glucose
(?100 mg/dl) is present. The discovery of multiple products released from
adipocytes, such as non-esterified fatty acids (NEFAs),
inflammatory cytokines, PAI-1, adiponectin and leptin has helped to build the
understanding of the relation between obesity and metabolic risk factors.
NEFAs are formed by lipolysis of
adipose tissue triglycerides. The greater the amount of fat in adipose tissue,
the more the amount of NEFAs released will be. Excessive influx of
non-esterified fatty acids leads to insulin resistance in the muscles and
increases the triglyceride content of the liver (fatty liver) (Scott M. Grundy,
2004).
The production of cytokines such
as TNF?, IL-6 is increased in obese persons and this interferes with the action
of insulin to suppress lipolysis. High PAI-1 levels in obese persons due to
abnormal abdominal adipose tissue or fatty liver, along with the high plasma
fibrinogen observed in such persons contributes to a prothrombotic state. Low
levels of adiponectin deprive obese patients the anti-inflammatory and
antiatherogenic properties necessary to fight against metabolic syndrome.
The most frequently observed
component of metabolic syndrome is abdominal obesity (when the waist
circumference is 102 cm or more in men or 88 cm or more in women). Metabolic
syndrome also known as Dysmetabolic syndrome or syndrome X is a major public
health challenge and is becoming more frequent due to the increased obesity
rates among adults in the past three decades. It may become the principal risk
factor for heart disease overtaking smoking which is currently the major risk
factor.
DIETARY
CHANGES
Carbohydrates, fats, and
proteins, which are the baseline nutrients are the basis of all life
activities. They form the carbon skeleton of various functional molecules, and
provide energy through oxidative decomposition. The main aim of nutrition is
preventing and treating nutritional deficiencies. However, when nutrition is disproportionate,
the body faces the problems of absorption and storage. Over nutrition, can not
only affect health but also cause many ailments such as diabetes,
cardiovascular diseases, obesity, hyperlipidaemia and hypertension.
Dietary changes in the past 30
years are predominantly characterized by increased consumption of animal
products, refined grains and sugars, due to the increased availability of
low-cost food and drinks, which are often low in nutritional value and high in
energy and sugar. Citing an example, global per capita food consumption was 2358
kcal per capita per day in the year 1965, and
increased to a 2655 in 1985 and a shocking 2940 kcal
per capita per day in 2015. It is expected to reach 3050 kcal per
capita per day by 2030. Furthermore, calories of different materials are not
the same depending on the metabolic pathways, like protein requires a higher energy
to get metabolize than fats and carbohydrates.
As many countries started to experience
rapid economic growth changes to food choice and availability brought about by
urbanization was inevitable, causing overnutrition. These conversions are also
fuelled by reductions in prices of low-quality foods that are high in energy
and increases in gross domestic product, which are indicative of higher family
income and greater purchasing power. Fast food has been linked to obesity, cardiac
and metabolic disease for a number of reasons, including high calorie content, huge
portion sizes, high amounts of processed meat, very refined carbohydrates,
sugary beverages, unhealthy fats, and unhealthy levels of salt and sugar.
The presence of overweight and
obesity is directly linked to the prevalence of metabolic syndrome,
cardiovascular disease and type 2 diabetes. This relationship is one of cause
(overweight/obesity) and effect (metabolic disease). Therefore, if added sugar
consumption promotes body fat gain relative to other macronutrients, this is a
second and indirect pathway by which high sugar diets may contribute to the
development of metabolic disease (Kimber L. Stanhope 2015).
ADDED
SUGARS
Added sugar at commonly-consumed
levels does not have a huge effect on the weight gain as per, but big on the
development of metabolic disease as we devour sugar treats almost every day in
variant forms. Sugar is not simply a source of extra calories. It is a direct
contributor to the development of metabolic disease. But some sugars pose a
greater threat compared to their counterparts. Excessive fructose ingesting
especially in combination with surplus energy intake does have adverse effects
on metabolic health, comparing glucose and fructose, glucose can be metabolized
by all the body's tissues, but fructose can only be metabolized by the liver in
any significant amount. Moreover, fructose from added sugars leads to higher
ghrelin levels also known as "hunger syndrome", reduced satiety, insulin
resistance, fat gain in the abdominal region, increased triglycerides and blood
sugar and small, dense low-density lipopolysaccharides compared to similar
number of calories from glucose. This knowledge and understanding will be more
effective in slowing our epidemics of metabolic disease.
OBESITY
MANAGEMENT
Obesity management is expensive and,
along with diabetes, obesity is a disease that needs to be defused. Medical
costs rise progressively as BMI increases and are expected to continue to rise
in the next 15 years. Obesity shortens life span and affects the function of
many organ systems. Mortality results from several diseases that are associated
with obesity, including diabetes, chronic kidney disease, gastrointestinal
disease, and cardiovascular disease and maintaining weight loss is often
difficult or unsuccessful. The first and foremost thing to manage obesity is to
control the diet and to consume appropriate foods. According to a study by Prof
George Bray MD, the energy intake should be reduced by 500 kcal/day below
energy requirements or must use a dietary plan that has 1200–1500 kcal/day for
women or 1500–1800kcal/day for men (increased by a further 300 kcal/day for
each sex if weight exceeds 150 kg) (Prof George Bray MD,
2016).
Even though, obesity is highly
preventable, the measures taken to control it is not as effective as it is
needed to be. When it cannot be prevented, treatment on various levels must be
indicated.
Physical activity, provides
only a small effect on weight reduction, still, it is an important part of
obesity management by conservation of the fat-free mass during severe weight
loss and additionally it helps to encourage weight maintenance. It increases cardiorespiratory
fitness. Physical activity counselling includes advice on both habitual
physical activity in everyday life and structured supervised exercise. Exercise
prescription must focus on a gradual increase to levels that are safe for the
patient. The prescription should be tailor made for each patient.
Dietary Prescriptions and dietary
modifications should be custom made. Moreover, it can be used to help the patient
identify insights and beliefs about cognition (emotional eating behaviour) and behaviour
(eating habits). The management of eating disorders also appears as an
imperative before reduction in energy intake. Weight maintenance would need spasmodic
treatment with formula diet or drug remedies.
Pharmacotherapy should
be considered as part of an all-inclusive strategy of disease management. It
can help to prevent the development of obesity co-morbidities (e.g. hypertension,
type II diabetes mellitus). Current drug therapy is suggested only for patients
with a BMI ? 30 kg/m2 along with an obesity-associated disease (e.g.
hypertension or type II diabetes mellitus). Medicines should be used according
to their licensed warnings and restrictions. Whether the therapy is useful or
not should be evaluated by the first 3 months and treatment should be sustained
only if weight loss achieved is considered reasonable (approximately 5% weight
loss in people without and 3% in patients with diabetes). Progresses in waist
circumference reduction should be used as alternative, more genuine indicator
for accomplishment. Treatment should be discontinued in non-responders. One of
the approved available drugs for weight management in Europe is Orlistat, which
is a triglyceride lipase inhibitor and it decreases fat absorption by 30%. It contributes
a modest effect to the lifestyle intervention when paired with hypocaloric
low-fat diet. Several other drugs are currently tested in clinical trials for
weight management worldwide. Soon such medicines are hoped to help bridge the
gap between existing treatment options and needs of the patients.
Bariatric surgery, when
used in carefully selected patients is the most effective measure for inducing
substantial weight loss. It is a part of a lifelong weight management programme
and might have a follow-up of medical complications. Current evidence points to
chief benefits in terms of prevention of type II diabetes, cardiovascular risk reduction
and cancer reduction (mostly in women), and suggests increased longevity. The
most frequently used surgical techniques now are adjustable gastric banding, sleeve
gastrectomy, Roux-en-Y gastric bypass, biliopancreatic diversion or combined
operations such as biliopancreatic diversion with duodenal switch. Proper communication
with the patient is essential regarding the risk-benefit ratio and an
experienced multidisciplinary team including the surgeon should cautiously
access the selection of the right patient for the procedure.
RECOMMENDATIONS
Strategies to address the global
obesity epidemic require sustained, population-wide intercessions and policy approvals
designed to improve diet and upsurge physical activity using a multilevel
systems approach. Battling obesity requires synchronized efforts from the
international community, governments, industries, health-care providers,
schools and universities, urban planners, agricultural and service sectors, the
media, communities and individuals. The agricultural and service sector can put
forth nutritional and agricultural policies, which can be powerful instruments
for preventing obesity if they are aligned with evidence-based national dietary
goals.
Legislation for removal of trans
fats from the food supply is an important factor and it should be enacted along
with replacing partially hydrogenated oils with oils that include omega-3 fatty
acids. This
initiative should be supported by government regulation, which could include inducements
for the production and use of oils that are healthier, but this approach would
require the agricultural and food industry sectors to work together. Implementation
of taxes on unhealthy foods and beverages must be indorsed by the government,
as well as the design and execution of food pricing policies, such as
agricultural subsidies, should stress the need to increase availability and
affordability of fruits, vegetables, legumes, nuts and whole grains. The
governments
should also encourage use of public transportation and bicycles by providing
incentives including discounted transportation fares, and secure bicycle
parking along with implementing taxes.
Voluntary actions and
regulations (labelling calorie and nutrient content of foods) made by industry
could be beneficial policies for improving diet quality both nationwide and
worldwide.
Growth in food marketing and
advertising, has created major shifts in food demand as marketing leads people
especially children to increase their consumption of advertised products. For
this reason, the WHO recommends that governments and industry decrease the advertising
and marketing of unhealthy foods and to improve the school meal programmes and
policies related to vending machines are influential tools to address childhood
obesity along with nutritional education about healthy diet and education about
active lifestyles. Make sure to deliver educational pamphlets to parents for
informed dietary choice.
Public-health messages about
healthy diet and lifestyle need to reach far and wide and this can only be
possible with the help of the mass media and public service campaigns, like Change4Life
in England, which aims in supporting people to make healthier choices about activity
and food.
CONCLUSION
Obesity has become an
international public health issue that affects the HALYs, risk of morbidity,
and raises health economics in countries all over the world. An
individual does not become obese acutely, it is likely that the risk factors
exist considerably long before evident indications of the metabolic syndrome
and cardio vascular disease are expressed. Some individuals carry the risk from
a very early age because of childhood obesity, while others do not reflect it
until later in life. Therefore, it becomes matter of importance to provide risk
inhibition to pre-symptomatic individuals.
Proper awareness must be spread
to the public, to eradicate any lingering myths and misconceptions regarding
the risk factors of obesity, how two calories are not the same and how diet and
added sugars affect metabolism.
Social inequalities and
stigmatization resulting in discrimination is very high for the obese patients.
Reducing weight stigma and access promotion to healthier lifestyle options are the
two vital points in management of the weight. The contemporary trends are
suggesting a co-responsibility which is shared by both the society and the
obese individual as it is hard to assess the accountability of an
individual for obesity or future weight gain.
REFERENCES
Brady, G., Frühbeck, G. Ryan, et al. (2016). D
Management of Obesity. The lancet,
387(10031), pp. 1947-1956
Fao.org. (2017). 3. Global
and regional food consumption patterns and trends. online Available at:
http://www.fao.org/docrep/005/ac911e/ac911e05.htm
Grover, S., Kaouache, M., Rempel, P., Joseph, L., Dawes, M.,
Lau, D. and Lowensteyn, I. (2015). Years of life lost and healthy life-years
lost from diabetes and cardiovascular disease in overweight and obese people: a
modelling study. The Lancet Diabetes
& Endocrinology, 3(2), pp.114-122.
Han, T. and Lean, M. (2016). A clinical perspective of
obesity, metabolic syndrome and cardiovascular disease. JRSM Cardiovascular Disease, 5.
Hanson, M., Gluckman, P. and Bustreo, F. (2016). Obesity and
the health of future generations. The
Lancet Diabetes and Endocrinology, online 4(12), pp.966-967.
Hensrud, D. (2004). Diet and obesity. Current Opinion in Gastroenterology, 20(2), pp.119-124 PubMed
Jebb, S., Aveyard, P. and Hawkes, C. (2013). The evolution of
policy and actions to tackle obesity in England. Obesity Reviews, online 14, pp.42-59.
Joseph, L., Dawes, M., Lau, D. and Lowensteyn (2015). Years
of life lost and healthy life-years lost from diabetes and cardiovascular
disease in overweight and obese people: a modelling study. The Lancet Diabetes
and Endocrinology, 3, pp.114-122
Kushner, R. and Bessesen, D. (2014). Treatment of the Obese Patient. 2nd ed. Springer.
Lim, S. (2017). Journal of Obesity & Metabolic Syndrome:
A New International Journal Targeting the Pathophysiology and Treatment of
Obesity and Metabolic Syndrome. Journal
of Obesity & Metabolic Syndrome, 26(2), pp.81-83. PubMed
Malik, V., Willett, W. and Hu, F. (2012). Global obesity:
trends, risk factors and policy implications. Nature Reviews Endocrinology, 9(1), pp.13-27.
Mela, D. (2005). Food,
diet and obesity. Boca Raton, CRC Press.
Mistry, S. and Puthussery, S. (2015). Risk factors of
overweight and obesity in childhood and adolescence in South Asian countries: a
systematic review of the evidence. Public
Health, 129(3), pp.200-209.
Mozaffarian, D. (2017). Foods, obesity, and diabetes—are all
calories created equal? Nutrition Reviews,
75 (suppl 1), pp.19-31.
Patterson, L., Kee, F., Hughes, C. and O'Reilly, D. (2014).
The relationship between BMI and the prescription of anti-obesity medication
according to social factors: a population cross sectional study. BMC Public Health, online 14(1).
Rhee, J., Mattei, J. and Campos, H. (2012). Association
between commercial and traditional sugar-sweetened beverages and measures of
adiposity in Costa Rica. Public Health
Nutrition, 15(08), pp.1347-1354.
Shridhar G, Rajendra N, Murigendra H, Prasad M. (2015).
Modern Diet and its Impact on Human Health. Journal
of Nutrition & Food Sciences, 05(06).
Spell, C. (2017). There's
no sugar-coating it: All calories are not created equal - Harvard Health Blog. online Harvard
Health Blog. Available at: https://www.health.harvard.edu/blog/theres-no-sugar-coating-it-all-calories-are-not-created-equal-2016110410602
Accessed 29 Nov. 2017.
Stanhope, K. (2015). Sugar consumption, metabolic disease and
obesity: The state of the controversy. Critical
Reviews in Clinical Laboratory Sciences, 53(1), pp.52-67. PMC
free article
Tappy, L. and Mittendorfer, B. (2012). Fructose toxicity. Current Opinion in Clinical Nutrition and
Metabolic Care, 15(4), pp.357-361.
World Health Organization. (2017). Obesity and overweight. online Available at: http://www.who.int/mediacentre/factsheets/fs311/en/
Accessed 27 Nov. 2017.
Yumuk, V., Frühbeck, G., Oppert, J., Woodward, E. and Toplak,
H. (2014). An EASO Position Statement on Multidisciplinary Obesity Management
in Adults. Obesity Facts, online
7(2), pp.96-101. Accessed 30 Nov. 2017.
