One important information to consider when researching different types of food is both the GI and the GL. Both are information that can be easily found on the Internet. GI (glycemic index) means how fast the blood glucose can rise after eating, and the GL (glycemic load) is based on the total amount of carbs in the food, which determines how long the spike will be. The more refined a food is and the longer it is cooked the highest will be the GI. 

The GI is a scale that goes from 0 to 100. Zero would mean that the food doesn’t raise the blood sugar at all (the list includes basically only water) and 100 means that the food raises the blood glucose as much as pure glucose (which is the theoretical maximum). Foods with a low GI (less than 55) raise the glucose gently, while foods with a medium (above 55) or high GI (above 70) cause violent spikes of glucose and insulin that can be harmful. 

Nowadays, most of us eat diets predominantly based on grains and potatoes, frequently with little vegetables and fruits. In some countries, it is common for many people to never buy fresh fruits and vegetables, since canned options are often cheaper, although unhealthier. As devotees we are often not much different from the general population: we eat little vegetables on the sabji (usually most potatoes), but not much more than that. 

This lack of vegetables and fruits in the diet can also weaken our health and contribute to many problems. The truth is that vegetables and fruits should be the main component of our diets, since the body simply can’t operate in an efficient way without a good quantity of it, due to the thousands of useful compounds they include. Although there is a general idea that our ancestors were eating mainly meat over the millennia, evidence shows that this is actually a myth. Human beings have been living on a diet rich in vegetables (be it due to agriculture, or to gathering) for millennia. Although meat was also present in most diets, the base in most cases were different types of vegetables, fruits, nuts, and roots. The human body is well adapted to the different compounds present on varieties of such ingredients and many important functions are compromised when they’re absent. They contain antioxidants, phytonutrients, vitamins, minerals, and other essential nutrients. A general rule is that we should eat one to two kilos of vegetables and fruits per day (it can be even more than that if good quality vegetables are available). Vegetables are generally better than fruits because fruits contain too much sugar. Fruits are also good but as a compliment. Vegetables should be the main focus. 

Recent studies show that the amount of vegetables one eats is the main indicator of one’s overall health. This is not difficult to understand based on the crucial importance of different vitamins, minerals, antioxidants, and phytonutrients for the operation of the body. Grains also contain some vitamins and minerals, the problem is that grains are very caloric, and thus you can’t consume a sufficient quantity of grains to satisfy your daily needs of such nutrients. One would need to eat 1.25 kg of whole grain rice to meet his daily needs of zinc, for example, without even speaking about the other nutrients. Vegetables and fruits, on the other hand, can be consumed in much more generous portions, and the secret to getting enough nutrients is exactly in the quantity.  

In recent decades the production of soybeans increased at a very accelerated pace. Most of it is used to feed livestock, but there is also a strong push to human consumption from the food industry. Soy is being marketed as a healthy protein, soy milk is being promoted as a healthier alternative to cow’s milk, and so on. However, is soy as good as they want us to believe?

The human body can adapt to many different types of diets. Over the centuries, populations would establish themselves in different environments and do their best to survive. In many cases, the diet would not be an option: they would just eat what was available. Nowadays, however, we have an abundance of food and we are in the unique position of being able to choose what we eat, thus sapience and a good deal of common sense became a necessity. 

To eat food fried on refined vegetable oil is not a very wise idea. One reason is that we end up eating a lot of refined vegetable oil, which will produce inflammation and other problems. On top of that, there are the toxic compounds produced when the oil is heated to high temperatures. 

Different from ghee and coconut oil, refined vegetable oils are rich in polyunsaturated fatty acids. Research shows that these unstable fats produce aldehydes (chemicals that are highly cancerogenic) as well as trans fats and other dangerous compounds when heated to high temperatures (Health effects of oxidized heated oils,  Foodservice Research International 13(1):41 – 55 · June 2006). A simple portion of french fries prepared on refined vegetable oil can contain up to 100 times the safe daily limit of aldehydes set by the World Health Organisation. 

In the previous parts, we saw the problems with sugar and wheat flour, both of which can be quite bad for our health when consumed in excess. What about rice?

Wheat has been a staple food in many societies for millennia. People were used to eating a lot of wheat in the form of bread, biscuits, pasta, etc. Some populations, like in many states of north India, had diets based on wheat (in the form of chapatis and rotis) and not much more. Still, until the 1950s people were relatively healthy, with few cases of diabetes, gluten intolerance, and cancer. This changed in the last few decades. 

The fact is that the wheat we eat changed radically in the last century. The first modification was an aggressive process of selection and hybridization of the wheat seeds. The plants became much shorter and the grains much bigger. While this resulted in great productivity gains (leading to the so-called green revolution), the resulting grains became very different from what people were eating in the previous centuries. The wheat became very rich in simple starches and the gluten content skyrocketed. At the same time, the content of vitamins and minerals became much lower. 

Few are going to disagree that sugar is bad for our health. Apart from being high-glycemic and favoring weight gain, another problem with sugar is that the body needs a lot of different minerals and other nutrients to metabolize it (it’s quite a complex process executed by the liver). Natural sources of sugar, like sugarcane and dates, are also rich in minerals, as well as fibers, therefore the body gets what it needs. When the sugar is refined, such nutrients are lost, and the body has to sacrifice its own stock of nutrients to metabolize the sugar, which leads to different problems. In other words, nature created fruits and vegetables rich in sugar as a package that contains what the body needs to metabolize it. The problems start when we dismantle the package and take only the sugar. 

In the 19th century, the US had a serious ecological crisis: after extracting the fibers, cotton planters were throwing the seeds in the rivers, creating pollution. As a response, the government passed a law prohibiting the practice. This became a problem for the planters, as the cotton seeds started to accumulate in their properties. For every 100 kilos of cotton fiber that one can get from the plants, there are 162 kilos of cotton seeds, so we can just imagine the huge piles of cotton seeds sitting in the farms.

Some intelligent man developed a technique to extract oil from the seeds, using chemical solvents. This oil was not considered edible, therefore it was sold as lamp oil. Since this oil was essentially made out of garbage, it was cheap to produce and therefore his company was able to make a good profit. 

Later, cheaper kerosene oil made from petroleum pushed him out of business. He had then one of these crazy ideas: Maybe instead of selling his oil as lamp oil, he could make people eat it! After perfecting the production of the cottonseed oil, and adding a hydrogenating process, he came up with something that could be used in place of butter or lard. This led to the creation of a product called Crisco, that made millions of dollars to the people involved.