An Inkling How Cooking Food Affect Gut Microbiome

Cooking Kills Antimicrobial Compounds Present in Raw Veggies

Food is the essence of life and each of us love to eat various foods in different preparation methods. Fruits and vegetables provide us with basic nutrients needed for sustenance and not all of us are fans of them. We try to dress up bananas in dripping honey or grind kale into a power juice before consuming. Some like it raw, some like it boiled and some others like it completely cooked with spices, salt and oil. The world does have some beings on this Earth who survive on raw food throughout their lives but these are a minority population. The majority of us, including myself relish cooked food.

The human microbiome has become more popular than before playing a critical role in everything from good health and weight changes to protection of the immune system and synthesizing certain vitamins and amino acids. Each of us have a unique network of microbiota which is entirely dependent on our DNA. We are exposed to these microorganisms during delivery in the birth canal and through mother’s milk. If this is surprising, reading through the entire process and the science behind it at www.firsteatright.com would amaze you even more. Hence, the microbes present in the mom are the sole determinants of those exposed to the child. As the kid grows, environmental factors and diet intake determine whether the microbiome is beneficial or hazardous.

Catching Over Cooking
We don’t have much power over environmental influence on our microbiome but we sure can make changes to the diet once we understand what is good and what is bad for out microbiome environment. There have been studies on how vegan, vegetarian or a meat-based diet affects microbiome composition; a high-fibre diet affects the type and number of microbiomes in the intestines and we do have a list of foods that can elevate the presence of good bacteria in our body.

While we can feel happy and proud of all the research done on these what is surprising is the fact that we don’t have any studies that have focused on how cooking itself alters the composition of the microbial ecosystems in our gut. This was taken up by a group of scientists at UCSF and Harvard University. The research team analysed the effect of cooking on the microbiomes of mice when they were fed with raw meat, cooked meat, raw sweet potatoes or cooked sweet potatoes. The diet included a combination of meat and tubers because previous studies have shown that cooking alters the nutrients and bioactive compounds in both differently. The results were somewhat surprising:
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1. Raw versus cooked meat did not show distinct effect on the animal’s gut microbes
2. Raw versus cooked sweet potatoes showed significant modifications to the gut microbial composition, microbe’s pattern of gene activity and metabolic products that they produced

The microbial changes could be due to two key factors: cooked food causes more calorie deposit in the small intestine leaving less for the hungry microbes down the gut and several raw foods contain potent antimicrobial compounds which can directly damage certain microbes. The way food is processed affects how our bodies digest food. Earlier, we used physical techniques like grinding and pounding to create hand-pounded rice and likewise which brough about more nutrient content to the consumer as the cells are disrupted in them. By cooking we are taking this process a step ahead as we are not only making a physical transformation but a chemical one as well-when you change the texture and process something that’s pretty hard to digest you are helping the individual by helping him/her complete a part of the digestion process outside the body and this helps the person digest the rest of the food in a much more efficient way. The difference between raw and cooked vegetables too is because plants produce a range of antimicrobial compounds that help defend itself but when they are cooked these compounds are inactivated. But when we eat them raw some of the antimicrobial compounds might act against microbes in the gut.

The researchers transplanted gut microbes from mice fed on both diets to germ-free mice that were fed a diet of standard chow. Those that received microbes conditioned on raw food gained more weight and body fat that the other group. This raises questions how the gut microbes would handle the antimicrobial properties of some raw vegetables and how foodborne antimicrobial compounds affect our health. Cooking might have more influence on the co-evolution between humans and resident microbes.
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Understanding completely how diet affects microbiome composition influences how gut microbes affect weight gain. The microbes have adapted themselves to the changing culinary culture and it needs to be seen whether this could have important side effects for modern health.