Why food matters and how can you benefit from a healthy diet?
We have been discussing quite a bit on the topic of immune system. Similar to sleep, diet plays a significant role and can have a huge influence on the functioning of the immune system. Balancing the inflammation is critically important to support healthy immune responses. While it is needed to produce inflammatory markers to combat infection / injury, it is also vital to dampen the inflammatory load to prevent unnecessary harm to the body. After all, the ability of the cells of the immune system to distinguish self from non-self is inevitably required in a well-functioning immune system.
Undeniably, food and nutrition are major input to our health and well being and it depends on how we make use of them to our benefit. There are foods that can create more pronounced inflammation in the body; conversely, some foods are helpful in suppressing the inflammatory cascade. When there are more pronounced inflammation going on in the body, your body tends to be more tired and fatigue as energy are diverted to manage the inflammation which would otherwise cause adverse health effects if it is not well-regulated. Another reason to start thinking about the impact food has on our general well being, not just for the immune health. [1,2]
As many of you would know, there are various types of “diet” out there that promotes their own uniqueness. It is not the interest of this article to discuss about the different diets, but to focus more on the topic of balancing the inflammatory responses in our system through food and nutrition.
Inflammation Vs Anti-oxidants
Generally, it is suggested to adopt a diet that has more anti-inflammatory properties in effort to lower the body’s inflammatory burden, and that could means to refrain from a westernized diet. [3,4] It would be logical to think that when one omit or reduce foods that can negatively affect the body inflammatory processes, it would be helpful in managing the overall inflammatory load. To illustrate, a research study documented even a single, high-fat processed meal (e.g., a meal consisting of white bread, butter, cheese, and a milkshake) can lead to an increase in the inflammatory cytokine interleukin-6 (IL-6) of around 100% relative to baseline within six hours of eating. A good example of how certain foods can increase the body inflammatory responses.
You may have heard about oxidative stress (a popular topic in recent decades in the field of nutritional science), which is the imbalance state that occur in our physiology when the body’s free radicals and antioxidant levels go off balance. While free radicals are normally produced during our metabolic processes; however, it must be properly balanced out by anti-oxidants in the body. In order to avoid being harmed by these oxidative compounds, a potential action step would be to avoid foods that capable to provoke inflammation and build on our body’s reserves of antioxidants. And general speaking, we can find antioxidants from vitamins or phytonutrients that are water-soluble (e.g., vitamin C) or fat-soluble (e.g., carotenoids, tocopherols, tocotrienols) available in nature, which has been shown to be abundant in plant-based foods. [5 – 10] At the same time,it is also important to know food categories with the lower content of antioxidants such as fats/oils, meats, poultry, fish/seafood, and eggs.
Do you know that abut 70% of our immune system is in the gut. Another word, the gut is actually a large immune organ.  Like many other healthy ecosystems, richness of microbiota species characterizes the gut microbiome in healthy individuals. Conversely, a loss in species diversity is a common finding in several disease states. 
The microbiome refers to the collection of genomes from all the microorganisms in the environment. Microbiota, on the other hand, usually refers to specific microorganisms that are found within a specific environment.
Getting a diverse blend of plant compounds is the key to vibrant health and stronger immunity. This is because the more diverse the diet, the more diverse the microbiome and the more adaptable it will be. [13,14] One significant action of the gut microflora is that they can be modified through dietary components and, ultimately, create significant impact on metabolic markers that relate to inflammation.
An interesting study that provide evidence that suggests diversity is a major factor was a study done on healthy women.  The women were divided into two groups, each consuming about the same number of servings of fruits and vegetables but with different levels of botanical diversity. One group was given five botanical families and the other group having selections from eighteen botanical families. While both diets were helpful in reducing lipid peroxidation, the group fed with higher diversity diet resulted in a significant decrease in DNA oxidation specifically.
Lipid Peroxidation is the oxidative degradation of fat. The process creates unstable fat radical,reacting with oxygen capable to result in cell damage.
Another study on Danish adults found that those who had a reduced diversity in gut microbiome has an inflammatory phenotype and greater metabolic dysfunction like adiposity, insulin and dyslipidemia.Therefore it is important to note that it is not just about ensuring the intake of plant-based foods in the diet, but to have a greater dietary diversity for better nutrient status. 
Simple Dietary Strategies to feed yourself better
- Avoid Westernized diet – Generally, try to avoid high intakes of red meat, processed meat, pre-packaged foods, butter, candy and sweets, fried foods, high-fat dairy products, eggs, refined grains, potatoes, corn (and high-fructose corn syrup) and sugary drinks. [18,19]
- Avoid processed, refined, sugar-sweetened food – This category of foods may be particularly harmful to your blood sugar metabolism, resulting in various metabolic dysfunctions. [18,19]
- Avoid excessive saturated fat and highly salted food – While fat is essential high amount of saturated fat combined with high inflammatory food components accelerate and exacerbate the oxidation of lipids in the body, that may potentially lead to arterial and vascular dysfunctions. [18,19]
- Increase intake of plant-based food (fruits and vegetables) – This will help to reduce the inflammation responses in the body (discussed above). 
- Increase intake of dietary fiber accordance to individual tolerance – Similarly, this help to promote anti-inflammatory responses in the body. However, those with bloating issue may not be comfortable with adding too much fiber to the body too quickly. Individuals with these issue may need to seek medical help and assistance from a healthcare provider.
- Increase your variety of fruits and vegetables – Don’t just eat the same food. It is not just about meeting the daily intake of fruits and vegetables, diversity is crucial in providing greater benefit from plant-based foods. 
- Adjust your food preparation methods – Grilling, frying, and broiling, as opposed to boiling and steaming, can create oxidative compounds referred to as advanced glycation end products (AGEs). Cook foods at lower temperatures and using moist methods of food preparation rather than dry and hot heat.[21,22]
As a general guide, dietary support discussed int this article aimed to provide you the idea on how dietary changes may help in reducing inflammation, increasing anti-oxidant levels and more importantly, the emphasize to you the importance on increasing the variety of your foods. The impact of dietary diversity is incredibly important and can be favorable to one’s general well being. 
*Please note: Due to the novelty of COVID-19, there is no absolute research data being published in regards to the effectiveness of dietary or lifestyle interventions for its prevention or treatment. Your individual and unique circumstances during this challenging time are well respected and empathized.The above information / recommendations are not specific to COVID-19 and are not intended to replace medical consultation with your healthcare provider.
*Reminder: You should always seek medical advice immediately from clinic or hospital if experience signs and/or symptoms related to Covid-19.
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- Emerson SR, Kurti SP, Harms CA, et al. Magnitude and timing of the postprandial inflammatory response to a high-fat meal in healthy adults: a systematic review. Adv Nutr. 2017;8(2):213-225.
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- Marion Salomé, Erwan de Gavelle, Ariane Dufour, Carine Dubuisson, Jean-Luc Volatier, Hélène Fouillet, Jean-François Huneau, François Mariotti, Plant-Protein Diversity Is Critical to Ensuring the Nutritional Adequacy of Diets When Replacing Animal With Plant Protein: Observed and Modeled Diets of French Adults (INCA3), The Journal of Nutrition, Volume 150, Issue 3, March 2020, Pages 536–545.
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