Importance of nutrition for maintaining a healthy lifestyle
Food is composed of macronutrients and micronutrients which are essential for growth, repair and energy. Protein is essential for growth, physical strength and muscular hypertrophy. The recommended allowance of protein is 0.8g / kg of body weight for a sedentary person which increases based on activity level (Wu, 2016). A deficiency in protein can lead to impaired growth and immunity, vascular dysfunction, weakness and anaemia (Wu, 2016). Meat products, dairy, beans and pulses provide a high amount of protein. Fat plays a vital role in growth and development and the maintenance of a healthy brain and nervous system. It is also essential for the absorption of fat-soluble vitamins such as A, D, E and K. Saturated fat should be kept to an intake of 20g per day, however individuals should increase their consumption of monounsaturated and polyunsaturated fatty acids. Monounsaturated fats include plant-based oils, nuts and avocados and are essential for improving a person’s cholesterol profile by lowering low-density lipoprotein (LDL) (Meehan, 2015). Polyunsaturated fats are also responsible for lowering LDL and consist primarily of omega 3s and omega 6s. Food sources include oily fish and vegetable oils (Meehan, 2015). Carbohydrates provide the body with energy and also stored energy in the form of glycogen and are essential for digestive health primarily through the role of fibre in the diet (Pearson, 2017). Numerous studies have also shown that the consumption of protein along with carbohydrate after resistance training increases muscle glycogen synthesis. One particular study found that ingestion of protein with carbohydrate after exercise lead to muscle anabolism compared to a placebo drink (Rasmussen, 2000), concluding that carbohydrates help to increase muscle protein synthesis.
Recent studies are showing a clear link between nutrition and chronic disease and it has become apparent that nutrient deficiencies are giving rise to energy imbalances (Kennedy, 2006). Nutrition is one of the most modifiable risk factors to help prevent chronic disease. Dietary Reference Intakes provide a model for assessing nutrient adequacy at both the population and individual level. While some of the deficiencies of macronutrients have been discussed, it is essential to also talk through micronutrient deficiencies. A deficiency can occur when the body does not absorb the required amount of a nutrient from food (Olsen, 2018). A number of health problems can occur that include loss of bone mineral density, impaired growth and digestion problems. Minerals are essential for the maintenance of homeostasis, for nerve function and healthy bones and teeth. A lot of minerals also work in synergy with various vitamins. The most common nutrient deficiency is iron which can lead to anaemia, causing fatigue and weakness (Olsen, 2018). Individuals may be getting adequate iron from their diet, but their body is weak at absorbing this mineral, thus it is advised to increase their intake of vitamin C to help with it’s absorption. Deficiency in B vitamins is also quite common such as thiamine deficiency which is essential for nerve and muscle function and niacin which helps in the conversion of food into energy and is thus essential for a healthy metabolism (Olsen, 2018). Another very common vitamin deficiency is vitamin D which affects 50% of the population worldwide (Nair, 2012). This is of huge public health concern as vitamin D is best absorbed via sunlight which is lacking in various European countries. It is not widely available in many foods. Hypovitaminosis D is associated with a higher incidence of chronic disease (Nair, 2012). Vitamin D is also essential for increasing the absorption of calcium from the intestine (Christakos, 2011). Thus a deficiency can lead to osteomalacia, increased fracture risk and softened bones.
Improvement in health parameters
Evidence based research has shown that there is lower onset of chronic disease and mortality rates in individuals who consume a Mediterranean diet which may include a larger amount of fruits and vegetables on a daily basis (Rasky, 2014). These individuals report a lower body mass index (BMI) and better quality of life. Studies have found that the daily consumption of nuts results in a lower mortality rate than those who do not consume them (Taliun, 2015). Walnuts are king of the nut family as they have a larger concentration of Docosahexaenoic acid (DHA) which is an omega 3 fatty acid and has been proven to promote brain health, improve cognitive performance and reduce ageing. There is a huge imbalance in the omega 3 to omega 6 ratio in the Western diet and it is advised to eat a higher amount of nuts and oily fish to increase the omega 3 levels in the body. Consuming nuts as part of a Mediterranean diet improves thinking and memory and also reduces inflammation (Kelly, 2016). Cardiovascular parameters are also improved, such as reducing hypertension. Coconut oil and palm oil were once thought of as being rather unhealthy in the diet and a marker for cardiovascular disease (CVD) as they are high in saturated fat. However recent research has shown that they possess a very high nutritional profile. Palm oil contains precursors for Vitamin A which helps in vision and the maintenance of tissues (Boateng, 2016). Vitamin E is also abundant in palm oil which acts as an anti-oxidant, thus boosting the immune system and helping reduce the prevalence of chronic conditions such as cancer (Boateng, 2016). Another benefit of using coconut oil is that it is relatively stable when heated and does not produce carcinogenic effects thus it is best used when cooking. Numerous studies have found that apricot kernels are effective at preventing and even treating cancer. They are hailed as a superfood, however receive a lot of bad press as they contain cyanide which is thought to be harmful to the body (Nichols, 2016). The seeds contain laetrile which is known to have anti-cancer properties because it contains one molecule of cyanide and one molecule of benzaldehyde which get activated at the cancer cell due to the presence of beta-glucosidase (White, 2014). This in turn is believed to destroy the cancer cell. There is much controversy over these seeds as they contain cyanide, however it has been shown that the cyanide is only active at the cancer cell and the presence of benzaldehyde protects healthy cells from damage. Laetrile is also abundant in the seeds of an apple which the majority of Westerners throw away. Mediterranean diets are naturally higher in fibre which helps reduce a number of disease sates such as bowel cancer and metabolic syndrome (MetS). A recent study in young South African adults found that an inadequate consumption of fibre increased the burden of MetS as it resulted in an increase in overall cholesterol and worsened fasting blood glucose levels (Sekgala, 2018).
Prevention of the onset of Metabolic Syndrome
MetS refers to a cluster of conditions that increases an individual’s risk of being diagnosed with CVD and type 2 diabetes mellitus. It is associated with greater adiposity particularly around the waist. MetS is largely linked to poor dietary choices and a sedentary lifestyle. The increased burden of obesity is associated with a rise in MetS. Diabetes is as a result of insulin resistance which causes higher than normal blood glucose levels. CVD can be characterised by hypertension and an unfavourable cholesterol profile which can lead to heart disease and stroke (Mayo Clinic, 2018). Usually an individual will exhibit reduced HDL-cholesterol, raised triglycerides and hypertension (Han, 2016). These parameters are all specific to weight gain and central obesity. MetS doubles the risk of CVD however it is a very modifiable risk factor which can result in remission with lifestyle interventions that result in weight management (Han, 2016).
Traditionally body mass index (BMI) has been used as a tool for the prediction of overweight and obesity however in more recent times waist circumference has been used as a more accurate indicator for disease states (Han, 2016). Those at highest risk have a waist circumference of 40 inches (males) or 32 inches (females) (Conrad, 2018). A reduction in weight by just 5 – 10% can improve health parameters and result in a reduction in disease risk. Weight gain with an increase in adiposity and an increase in fat mass in the intra-abdominal area is an indicator of MetS (Han, 2016). This includes ectopic fat that surrounds the vital organs such as the liver, pancreas and heart.
CVD is the leading cause of death in the Western world. Individuals with CVD often exhibit signs of dyslipidaemia and hypertension (Han, 2016). The main cardiovascular conditions include angina, artherosclerosis, hypertension, high cholesterol and stroke. Artheroscelrosis is characterised by the build up of plaque within the arteries due to the deposition of fatty deposits such as cholesterol (Irish Heart Foundation, 2018). Prevention is more favourable than treatment and involves certain lifestyle changes such as improving one’s diet and getting more physical activity. Dyslipidaemia is characterised by an elevation of cholesterol and triglycerides in the blood which can be due to poor dietary choices or the prolonged increase of insulin levels. Dyslipidaemia plays a central role in the development of artheroscelrosis which is caused by a build up of plaque and it also contributes to other cardiac events (Hendrani, 2016). Lifestyle changes such as stopping smoking, improving one’s diet and getting more physical activity can improve the outcome for the individual and reverse the signs of dyslipidaemia. If changes are not made on an individual level then pharmacologic treatment may be used such as administering statins (Hendrani, 2016).
Hypertension is characterised by a variability in blood pressure where individuals will experience elevated systolic and diastolic blood pressure. While an increase in insulin levels is one of the contributors to dyslipidaemia, it is also associated with hypertension, thus there is a causal link between hypertension and MetS (Zanchetti, 2018). A prehypertensive individual will experience systolic blood pressure just above 120 mm Hg and diastolic blood pressure just above 80 mm Hg. The progression of the condition will result in a higher recording as the person develops stage 1 or stage 2 hypertension (Barnes, 2018). The higher an individual’s blood pressure means they have a greater risk for heart disease and stroke (Irish Heart Foundation, 2018). A stroke occurs when blood vessels which carry oxygen to the brain become blocked or burst. Every year more than 10,000 people in Ireland have a stroke (Irish Heart Foundation, 2018). Individuals with high stress levels, inactivity, high BMI and are smokers are at increased risk of developing a stroke thus it is paramount to make lifestyle adjustments. Age, gender and family history also contribute to the likelihood of developing a stroke and are unfortunately unmodifiable risk factors. Hypertension can be prevented if one aims to maintain a healthy BMI and improves their diet, including a reduction in their salt intake. Obesity is associated with the increased prevalence of hypertension, however not all individuals who are obese will go on to develop the condition (Zanchetti, 2015). A large epidemiological study in China found that the measurements of visceral fat to body fat percentage provide a better understanding for the risks of developing hypertension (Zanchetti, 2015). Another randomised controlled trial showed that the modification of sodium to potassium levels in the body has an impact on hypertension with potassium supplementation reducing blood pressure, while an increase in sodium increased it (Zanchetti, 2015). Engaging in physical activity on a regular basis is also paramount in lowering blood pressure.
The growing burden of type 2 diabetes is one of the leading causes of mortality worldwide and is one of the most modifiable disease states when adopting long-term lifestyle changes such as dietary interventions and exercise adherence. The risks of developing diabetes is greater when glucose levels are beyond a certain threshold (Pratley, 2013). Diabetes is characterised by a fasting blood glucose of 5.5mmol/L or above (Barnes, 2018). When an individual experiences pre-diabetes, early intervention is paramount in order to reverse their condition. The challenge with this however is that the early stages of the disease are asymptomatic and it may be difficult to detect the condition (Pratley, 2013). Regular blood test screening can help detect the occurrence of pre-diabetes by estimating fasting blood glucose levels. Unfortunately today, in clinical practice, dietary recommendations that have little supporting evidence for the treatment of diabetes are still being used (American Diabetes Association, 2002). It is essential that the best dietary advice takes into account individual circumstances and preferences when designing a nutrition programme. The awareness of the benefits of nutrition therapies must be ingrained in the individuals with diabetes (American Diabetes Association, 2002). The aim of dietary intervention is to restore blood glucose levels to that below 5.5mmol/L, to improve their HDL and LDL cholesterol profile and to reduce the prevalence of hypertension. It is well known that the high consumption of high glycemic carbohydrates such as simple sugars is one of the contributors to the onset of diabetes. However more recent research has indicated that the onset of diabetes type 2 is more prevalent in meat eaters, especially those that consume a large amount of processed meats (Feskens, 2013). An increase in CVD and stroke is also associated with a higher consumption of meat. Thus it may be beneficial to consume a higher amount of oily fish, nuts, beans, lentils and pulses which are all protein and iron rich and provide an abundance of vitamins and minerals to the diet.
While it may seem simplistic to make dietary changes and exercise more in order to achieve a healthy BMI and reduce overall mortality risk, various challenges stand in the way. It is obvious that there are barriers to change seeing as the global obesity epidemic is getting worse rather than better. A primary challenge for individuals is the increased burden of severe mental illness (SMI). There is a causal link between obesity and SMI and thus behavioural and lifestyle interventions are paramount (Sharma, 2012). The possible causes of overweight and obesity include pharmacologic treatment to control symptoms, lifestyle such as inactivity and poor dietary choices and binge-eating comorbidity (Alda, 2009). There has been a marked increase in the use of anti-psychotics in recent times to control mental illnesses such as bipolar disorder, acute psychosis and schizophrenia. These drugs act as dopamine antagonists and thus the individual receiving treatment will have less dopamine circulating and will thus experience reduced reward, motivation, pleasure and energy in their daily life. Antipsychotics are known to improve the hedonic reward response of food which is used as a stimulant to receive pleasure while undergoing treatment (Elman, 2006). Individuals experience intense cravings for refined carbohydrates and sugar due to the imbalance that the drugs provide to neurotransmitters in the brain, namely dopamine.
While undergoing pharmacologic treatment for SMI, it is of huge importance that psychiatrists and nursing staff measure the patient’s BMI during each doctor visit by simply recording their height and weight. In this way they will see if they are gaining fat mass at a rapid rate and can thus intervene with stressing the importance of dietary and exercise adherence in order to maintain a healthy BMI. Unfortunately the increased risk of overweight and obesity among those with SMI is the primary reason that they have a shorter life expectancy than the general population.
Outline why a person should focus on whole food sources
Whole foods are foods which undergo minimal processing, have less additives, saturated fat, salt and sugar and have a higher amount of nutrients and fibre. Fruits, vegetables and whole grains are prime examples of whole foods. Cardio-metabolic disease and cancer are two of the leading causes of death worldwide and it has been postulated that a higher consumption of whole foods such as fruit, vegetables and other plant sources helps in the prevention of CVD, diabetes, cancer and alzheimer disease (Liu, 2003). Whole foods such as fruit and vegetables contain an abundance of bioactive compounds such as phytochemicals which are vital for their potent antioxidant properties (Liu, 2003). This makes them both anti-cancerous and immune-boosting. Human cells are constantly exposed to a wide variety of oxidising agents which lead to the formation of free radicals in the body. This leads to oxidative stress and can cause DNA damage and ageing which accelerates disease states such as CVD and cancer (Liu, 2003). Whole foods are vital in the diet for their anti-oxidant properties.
Whole grains are also essential in the diet and consist of bran, germ and endosperm which make up their original composition (Okarter, 2010). Increased consumption of whole grains is associated with a reduced risk of chronic disease such as CVD, diabetes and some form of cancers. They too contain an abundance of phytochemicals with anti-oxidant benefits (Okarter, 2010). Whole grains are also abundant in lignans and phytoestrogens which have a protective role in fighting hormone-related diseases such a cancer (Thompson, 2009).
While food additives can sometimes have some nutrient value, the bulk of additives are quite detrimental to one’s health as they contain a high amount of salt, monosodium glutamate and citric acid. They are used to enhance the flavour or appearance of food and to preserve many foods (Food Additives, 2018).
The Mediterranean diet has long been reported to be associated with a reduced prevalence in chronic disease and overall mortality. A Mediterranean diet is one which incorporates more whole foods and less refined and processed food. Prospective studies have shown the adherence to such a diet protects against cancer, neurodegenerative disease and cardio-metabolic disease (Sofi, 2010). A Mediterranean diet is popular in Greece, Spain and Italy and they consume large amounts of fruit and vegetables, whole grains, oils, avocado, nuts and fish. In comparison, the majority of the Western world is adopting a Standard American Diet (SAD) with too much saturated fat, refined carbohydrates and sugar. It is this type of diet that is contributing to the global epidemic of obesity and MetS at an alarming rate. The food pyramid was updated in 2016 to include an abundance of fruit and vegetables at the bottom of the food pyramid. This replaced carbohydrates such as bread, pasta and cereal which moved up a shelf. There is still an emphasis on limiting sugar and saturated fat intake which remain at the top of the food pyramid.
Focus on Nutrition rather than fad diets
A fad diet is one which promises rapid weight loss by adopting an unhealthy food plan and eliminating certain food groups or cutting calories to an unsafe level (Barnes, 2018). The Atkin’s diet, intermittent fasting diet and the grapefruit diet are three popular diets used today which are followed in the hope of dropping pounds fast in the build up to an upcoming event. While following a fad diet such as the above will result in quick weight loss, the weight is usually regained at a rapid rate once the diet is stopped as the diet is usually unsustainable and cannot be incorporated into a long-term healthy eating plan (Barnes, 2008).
Atkin’s is a very low carbohydrate diet, also known as a ketogenic diet (KD) as the body goes into a state known as ketosis once carbohydrate sources are almost eliminated. This state is known to burn fat at a high rate, as there is no glucose present in the body and thus the body will target fat cells first. Many studies have shown various health benefits of such a diet, including the benefit of reducing seizure occurrence in patients with epilepsy (Miranda, 2011). One such study compared the use of a modified atkins diet (MAD) with a KD and found that the MAD was almost as effective as a KD diet in reducing seizure occurrence in children with medicine resistant epilepsy (Miranda, 2011). A MAD is one that is not as strict as a KD and thus may be easier to implement and follow. The MAD was evaluated on 33 children with epilepsy and found that after just 3 months 52% of the children were responders, in that they saw a marked decrease in their seizure frequency of 50% or more (Miranda, 2011). It has also been postulated that KD can reverse or reduce the symptoms associated with CVD and type 2 diabetes. The KD results in a positive increase in total HDL cholesterol which significantly improves one’s cardiovascular health. The elimination of carbohydrates also combats insulin resistance in the fight against type 2 diabetes (Paoli, 2013). The primary reason for adopting a KD is for rapid weight loss, however unfortunately the majority of the weight loss is seen in the first week as the body eliminates 3 – 4 pounds of water weight due to the elimination of carbohydrate. This water weight will reappear straight away once the individual eats a high carbohydrate meal and this may cause them to get discouraged and give up on the diet. KD are also lacking in fibre primarily coming from whole grains, fruit and vegetables and are thus low in many essential vitamins and minerals (Barnes, 2018).
Intermittent fasting involves extended periods of not consuming any food in the hope that the body will go into fat burning during that time. The most popular of this is the 16:8 diet which allows a window of eight hours for feeding and 16 hours of fasting. The biggest advantage to such a diet is the secretion of insulin-like growth hormone 1 (IGF-1) which slows down the ageing process (Barnes, 2018). The 5:2 diet is another popular type of intermittent fasting where an individual eats normally for five days of the week, but reduces their overall calories to no more than 500kcal per day for two days. Studies have shown that both types of diet increase longevity in monkeys and reduce comorbid obesity in humans (Mattson, 2005). Studies have shown that these diets improve cardiovascular and brain health by reducing coronary artery disease and stroke (Mattson, 2005). While these diets may improve overall health parameters they may take a while to adjust to due to frequent bursts of hunger signals. They are also not well suited to athletes or those who engage in intense physical activity as these individuals may require more regular feeding patterns.
In order to maintain a healthy weight, it is recommended to focus on a diet rich in whole foods, healthy fats and good sources of protein. Individuals should also aim to become more physically active. A healthy and sustainable weight loss is one which is slow and steady and does not result in rebound weight gain. Nutritionists and dieticians will all recommend a weight loss of one to two pounds per week which involves a caloric deficit of between 500 calories and 1000 calories per day. This is achieved through reducing overall food intake and engaging in more physical activity.
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