Nutrition and Immunity Part 3 PDF

Nutrition and immunity Part 3 By Dr. zainab saeed aly  Balanced diet A balanced diet is one that includes all food groups in a way that respects the amounts of carbohydrates, proteins and fats. Additionally, it includes the importance of dr...

Nutrition and immunity Part 3 By Dr. zainab saeed aly  Balanced diet A balanced diet is one that includes all food groups in a way that respects the amounts of carbohydrates, proteins and fats. Additionally, it includes the importance of drinking water every day and exercising. person Calorie requirements Males: 9–13 years 1,600–2,600 Active females: 14–30 years 2,400 Sedentary females: 14–30 years 1,800–2,000 Active males: 14–30 years 2,800–3,200 Sedentary males: 14–30 years 2,000–2,600 Active people: 30 years and over 2,000–3,000 Sedentary people: 30 years and over 1,600–2,400 The ideal proportions of macronutrients in the diets of men and women are as follows, according to the 2020 USDA Dietary Guidelines for Americans: 45-65 percent of daily calories coming from carbohydrates 10-35 percent from protein 20-35 percent from fat (less than 10 percent of which should come from saturated fat)  Vegetarian diet The vegetarian diet involves abstaining from eating meat, fish, and poultry. People often adopt a vegetarian diet for religious or personal reasons, as well as ethical issues, such as animal rights. A vegetarian diet focuses on plants for food and includes a variety of protein-rich plant foods like whole grains, legumes, tempeh (a sweet from soya bean), tofu. The most common types include: Lacto-ovo-vegetarian diet: eliminates meat, fish, and poultry but allows eggs and dairy products Lacto-vegetarian diet: eliminates meat, fish, poultry, and eggs but allows dairy products Ovo-vegetarian diet: eliminates meat, fish, poultry, and dairy products but allows eggs Pescatarian diet: eliminates meat and poultry but allows fish and sometimes eggs and dairy products Vegan diet: eliminates meat, fish, poultry, eggs, and dairy products, as well as other animal- derived products, such as honey Flexitarian diet: a mostly vegetarian diet that incorporates occasional meat, fish, or poultry tofu tempeh Side effects: Vegetarian diets do not contain meat, poultry or fish; vegan diets further exclude dairy products and eggs. This makes vegetarian diets usually rich in carbohydrates, n-6 fatty acids, dietary fibre, carotenoids, folic acid, vitamin C, vitamin E and Mg, and relatively low in protein, saturated fat, long-chain n-3 fatty acids, retinol, vitamin B(12) and Zn; vegans may have particularly low intakes of vitamin B(12) and low intakes of Ca. NB: Omega−6 fatty acids (also referred to as ω−6 fatty acids or n−6 fatty acids) are a family of polyunsaturated fatty acids ❑Animal proteins supply Essential Amino Acids more effectively than plant proteins. ❑Low digestibility of plant proteins may result in nutritional deficiency for infants and young children ❑Plant proteins are more hydrophobic, aggregated and inflexible than animal proteins. ❑In general, plant proteins offer lower nutritional values due to unbalanced amino acid composition (e.g. lack of some Essential Amino Acids (EAAs), such as lysine), and slow or ❑reduced digestibility. However, they still provide a good protein source for humans and can contribute to a balanced diet. Important notes about protiens: ✓Amino acids are building blocks of proteins and are determinant of their structure and ultimate predictor of protein’s biological functions. ✓the number and sequence of amino acids are determinants of protein biological functions and other characteristics attributed by them. ✓All proteins found in living organisms are made of only 20 types of L-amino acids ✓With respect to essentiality, amino acids are divided into two categories, essential or indispensable amino acids which cannot be synthesized in human body, nine amino acids – histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine – and are always needed to be taken from exogenous sources ✓non-essential amino acids – alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid , glutamine, glycine, proline, serine, and tyrosine – which can be synthesized in the body from non-protein sources like carbohydrates and lipids or modifying other amino acids ✓Cellular protein synthesis in the body to perform various biological functions is always based on “all or none principle” showing that all amino acids are required to synthesize a protein. ✓In case of defciency of one essential amino acid in the body, the process of protein synthesis will not be completed ✓the quantity and quality of protein are equally important to perform metabolic functions of the body. It is evident that protein quality varies among different protein sources due to the difference in ratio of amino acids present in specifc protein sources. The quality of a protein in a food is dependent on its amino acid contents, especially essential amino acids (EAAs) and their bioavailability in circulation after digestion and absorption to maintain normal body composition and function throughout the life cycle. In case of cellular protein synthesis, protein quality has more importance as compared to protein quantity. So, the protein quality infuences protein requirement of a person; higher the quality, lower the protein requirement. ✓The quality of protein in human nutrition is also expressed as Amino Acid Score (AAS); the content of EAAs and their capacity to fulfll body’s requirements. The AAS is defned as “ratio of its content of EAA to the amount required”. ✓all animal source proteins have a remarkably more score for all parameters than plant proteins. Almost all animal sources have a PDCAAS(Protein Digestibility- Corrected Amino Acid Score ) value of near to 1 while in plant sources only soy and canola have values comparable to animal foods ✓On the basis of provision of the EAA, protein sources are divided into two categories, i.e., “high quality or complete proteins” which provide all EAAs in appropriate quantities and “low quality or incomplete proteins, in which one or more EAAs are defcient. In general, animal proteins are considered as high-quality proteins due to their amino acid pattern closer to human body requirements as well as good digestibility and provide all nine EAAs in adequate amounts ✓Wheat, rice, corn, nuts and other grains and seeds are defcient in lysine and sometimes in threonine and tryptophan as well, whereas methionine is the limiting amino acid in legumes, peas, lentils and vegetables (Gropper et al. 2018). If planned poorly, a diet limited to only low- quality proteins may lead to EAAs defciency resulting in the body’s inability to produce cellular proteins which may lead to metabolic malfunctioning in the body. ✓To provide all EAAs to the human body as per requirement is crucial and it can be achieved through increased protein intake, supplementation with limiting amino acids and blending with different plant as well as animal source proteins. For example; legumes have high content of lysine but defcient in methionine, so can be combined with cereals which are limited in lysine but have more than adequate amount of methionine and. ✓Animal protein sources on the basis of per unit weight or per unit energy, are considered as richer source of six micronutrients than plant sources with good digestibility and bioavailability; vitamin A, ribofavin (B2), vitamin B12, iron, calcium and zinc as compared to vegetarian diets. Thus, foods from animal sources fill multiple micronutrient gaps at a lower volume of intake than the plant source foods  Intermittent fasting Intermittent fasting is an eating pattern that includes hours or days of no or minimal food consumption without deprivation of essential nutrients. During the fasting periods, you won’t eat anything. You can usually drink calorie-free beverages like water, herbal tea, and black coffee. These are the most popular methods: 1. The 16/8 method: Also called the Leangains protocol, this involves an 8-hour eating period and a 16-hour fasting period. Some people do this by skipping breakfast, but you can also do the reverse and skip dinner or eat early. 2. Eat-stop-eat: This involves fasting for 24 hours once or twice per week. Because this is a slightly more advanced version of fasting, you should only try this if you’re pretty comfortable with the practice. 3. The 5:2 diet: With this method, you consume only 500–600 calories on two non consecutive days of the week but eat as usual the other 5 days. Body changes occurring at molecular and cellular levels with fasting HGH: levels of HGH(human growth hormone) increase. This can help with both fat loss and muscle growth. Insulin: insulin sensitivity improves and levels of insulin decrease. Lower insulin levels make stored body fat more accessible. Cellular repair: When fasted, cells initiate cellular repair processes. This includes autophagy, which means cells digest and remove old and dysfunctional proteins that build up inside them. NB:Autophagy is a natural, self-preservation mechanism whereby the body removes damaged or dysfunctional parts of a cell and recycles other parts toward cellular repair. Gene expression: Fasting can cause changes in the function of genes related to longevity and disease prevention. norepinephrine (noradrenaline):IF increases the release of this fat-burning hormone and because of these changes, short-term fasting may temporarily increase the metabolic rate. Ketogenesis: fasting triggers the body to switch its source of energy from glucose stored in the liver to ketones, which are stored in fat  Herbals and immunity Green tea: Green tea is a type of tea that is made from Camellia sinensis leaves. It is widely cultivated around the world. oSteeping, or brewing, is the process of making tea from leaves and hot water, oSteeping too hot or too long results in the release of excessive amounts of tannins, leading to a bitter, astringent brew, regardless of initial quality. T oGreen tea is exceptionally high in polyphenols, particularly catechins, which are a type of antioxidant. oThe most notable catechin in green tea is epigallocatechin gallate (EGCG), known for its potent health-promoting properties. There are several remarkable features and benefits of green tea: 1) its ability to enhance cognitive function. ▪This benefit is largely due to its caffeine content, that works by blocking adenosine, a neurotransmitter that promotes sleep, thereby increasing alertness and focus. Additionally, It contains L-theanine, an amino acid that promotes relaxation without drowsiness. This unique combination of caffeine and L-theanine can lead to improved attention span and cognitive performance. ▪Research indicates that regular consumption may enhance memory and learning capabilities 2) Promote Calm and relaxation its calming effects, primarily attributed to L-theanine.This amino acid increases the production of neurotransmitters such as GABA, dopamine, and serotonin, which are crucial for mood regulation. By enhancing these brain chemicals, L-theanine helps reduce stress and anxiety levels while promoting a sense of tranquility. 3) Protect the Brain andpromotes neuronal health attributed to its high concentration of catechins, especially epigallocatechin gallate (EGCG), a powerful antioxidant It inhibit the formation of beta-amyloid plaques, which are characteristic of Alzheimer’s disease 4) Support Blood Sugar Control opolyphenols in green tea can improve insulin sensitivity and reduce blood sugar levels ocatechins may inhibit enzymes involved in carbohydrate digestion, thereby reducing glucose absorption in the intestines. 5) Reduce the Risk of Heart Disease oimproved endothelial function oits anti-inflammatory properties othrough lowering the levels of LDL cholesterol while increasing HDL cholesterol The mechanisms behind the tea’s cholesterol-lowering effects are multifaceted. ✓Firstly, catechins can inhibit the absorption of cholesterol in the intestines, thereby reducing the amount of cholesterol that enters the bloodstream. ✓Additionally, this beverage has been shown to enhance the activity of LDL receptors in the liver, promoting the clearance of LDL from circulation 6) Support Bone Health ✓Its antiinflamatory effect ✓Stimulating osteoblasts activity ✓Inhibiting osteoclasts activity 7) can modulate levels of ghrelin (the hunger hormone) and leptin (the satiety hormone), potentially leading to reduced food intake. 8) Improve Gut Health: regular consumption of green tea can encourage the proliferation of good bacteria in the intestines, thus enhancing overall gut health. the tea has been shown to improve gut barrier by strengthen the intestinal lining, reducing permeability and preventing harmful substances from leaking into the bloodstream.  Leaky gut Leaky gut is a condition in which bacteria and toxins “leak” through the intestinal wall. Though many medical professionals do not recognize it, scientific evidence suggests it is related to many health issues. The walls of the intestines act as barriers, controlling what enters the bloodstream to be transported to organs. Small gaps in the intestinal wall called tight junctions allow water and nutrients to pass through, while blocking the passage of harmful substances. Intestinal permeability refers to how easily substances pass through the intestinal wall. When the tight junctions of intestinal walls become loose, the gut becomes more permeable, which may allow bacteria and toxins to pass from the gut into the bloodstream. This phenomenon is commonly referred to as “leaky gut.” ❑When the gut is “leaky” and bacteria and toxins enter the bloodstream, it can cause widespread inflammation and possibly trigger a reaction from the immune system. ❑Supposed symptoms of leaky gut syndrome include bloating, food sensitivities, fatigue, digestive issues and skin problems ❑A protein called zonulin is the only known regulator of intestinal permeability. ❑When it’s activated in genetically susceptible people, it can lead to leaky gut. Two factors that trigger the release of zonulin are bacteria in the intestines and gluten, which is a protein found in wheat and other grains There are likely multiple contributing factors to leaky gut syndrome. ✓Excessive sugar intake: An unhealthy diet high in sugar, particularly fructose, harms the barrier function of the intestinal wall. ✓Non-steroidal anti-inflammatory drugs (NSAIDs): The long-term use of NSAIDs like ibuprofen can increase intestinal permeability and contribute to leaky gut. ✓Nutrient deficiencies: Deficiencies in vitamin A, vitamin D and zinc have each been implicated in increased intestinal permeability ✓ Inflammation: Chronic inflammation throughout the body can contribute to leaky gut syndrome. ✓Stress: Chronic stress is a contributing factor to multiple gastrointestinal disorders, including leaky gut. ✓Poor gut health: There are millions of bacteria in the gut, some beneficial and some harmful. When the balance between the two is disrupted, it can affect the barrier function of the intestinal wall. ✓Yeast overgrowth: Yeast is naturally present in the gut, but an overgrowth of yeast may contribute to leaky gut.