Difference between revisions of "Common Whole-food Staples"

Latest revision as of 21:32, 24 June 2021

A food staple is a food that is eaten routinely and is considered the 'staple' of a meal, because it consists of the biggest amount of calories and volume found in the meal.

This section will talk about all the common vegan food staples and how healthy they are. All of these staples can be used as the main caloric source of vegan recipes--as their plain taste combined with their cheap prices and the large array of nutrients they have makes them a good choice for the main source of calories in a diet.

The foods will be sorted by value of nutrient density per kcal, which is decided according to protein, vitamin B complex, vitamin A, calcium, iron, potassium, and zinc levels (more explained below). A couple of processed staples (e.g. white pasta and white rice) will be also included for comparison.

It is sorted by calories, instead of weight or volume, because caloric intake is the most prevalent and important metric in food plans, important to know to be able to fit all the required nutrients inside our usual daily caloric intake. Therefore, foods with the highest nutrient density per kcal are ranked higher, because they would make fitting all the nutrients we need in our daily caloric intake easier.

When taking into consideration the nutrients to determine how good a staple is, proteins, omega-3, omega-6, vitamin B complex, vitamin A (expressed in RAE), vitamin E, calcium, iron, potassium, and zinc are the ones observed--this is because these represent both the nutrients that are mainly sourced from staples (and usually less so from other foods), and the nutrients that are usually not easy to get enough of.

A higher value is placed on calcium and zinc (calcium as the highest), as those are usually the hardest target to hit. Potassium is given a lower weight because, while hitting the recommended 4700mg/day RDA is very hard, 3400mg/day is an already sufficient RDA, and hitting a high enough value of potassium is easier on a vegan diet than not. Iron is given a higher weight than potassium because, while usually getting enough iron is pretty easy, iron has a worse absorption rate than on a non-vegan diet by a multiplier of 0.65-0.8 (if you want to read more about it), not eating vitamin C alongside iron-rich foods or drinking caffeinated drinks close to iron-rich meals affects the absorption of iron negatively by a very significant amount, iron is often sourced mainly from staples, and women during the menstrual cycle can easily get iron deficient. So, all in all, it is better to play it safe and give iron a significant enough weight--and while being a male that does not drink caffeinated drinks, eats vitamin C-rich foods alongside meals, and eats a good amount of food (good amount of iron) throughout the day would mean there is no worry whatsoever for iron, that is not always the case.
Protein is given a low weight, because it is very easy to reach the RDA of it, but still important enough because it is mainly sourced from staples and more of it correlates with feeling more full.
Vitamin B complex is given a lower weight than vitamin A and vitamin E, as vitamins A and E are usually harder to hit if not eating specific vitamin A/E-rich foods, while B vitamins can be had in good quantities from plenty of foods (but staples are usually still the main source). Vitamin B complex is calculated as the average %RDA of the B vitamins, to give a good idea of how rich/poor a food is in B vitamins; (B1% + B2% + B3% + B5% + B6% + folate%) / 6.
Fiber is not considered because it is very easy to get enough fiber on a vegan diet, and while there are more benefits with more fibers, it is not a highlight nutrient to go after with staples.
Omega-3's RDA is hard to hit if not eating specifically omega-3-rich foods, similarly to vitamin A, E, and iron, so it has been given the same weight as those.
Omega-6, instead, has a significantly lower weight, because it is very easily obtained through processed foods and added oils--and while a fully whole-foods diet would not have those (in which case a higher attention would have to be placed on meeting the RDA of omega-6), people generally do include some processed food products in their diet and/or add some oils to their cooking.

Vitamins A and E's absorptions are significantly affected by the amount of fat present in the meal, and studies support 6g of fat as the optimal amount of fat required in a salad for full absorption of fat soluble vitamins (vitamin A and vitamin E). [1]
Thus, when considering vitamins A and E, a lower absorption rate is considered according to how much fat the food has--and as the study says, the absorption becomes almost negligible without any fat.
However, because we cannot know what foods components would go in a full meal, assigning a x0 or a x0.1 multiplier to fat soluble vitamins in staples without fats is not realistic, as it would be reasonable to believe that some fats would be present in most meals, be it with condiments, or fat-containing foods on the side and/or in the recipe.
Considering this, we have assigned a x0.5 multiplier to the absorption of fat soluble vitamins when there is 0g of fat in the staple (no fat whatsoever), and an optimal x1 multiplier when the amount of fat is optimal for full absorption.

To understand how much fat would be optimal for full absorption, we can take into consideration the study mentioned above--for lack of better data on this subject--, where in a salad with 119% RAE (vitamin A), the vitamin A was considered to have optimal absorption with 6g of added fat. For sake of playing it safe and having an easier time with numbers, the amount of fat required for optimal absorption of 100% RDA of RAE (vitamin A) is left at 6 grams.
That can be extrapolated to different %RDA numbers of vitamins A and E, proportionally increasing/reducing the optimal-amount-of-fat-for-absorption according to how proportionally higher/lower the %RDA of a fat soluble vitamin is compared to the 100% RDA = 6g of fat (100% RDA : 6 grams of fat = x% RDA : y grams of fat). For example, 20% RDA of vitamin A can be assumed to require 1.2 grams of fat to have full absorption, 10% RDA can be assumed to require 0.6 grams of fat for full absorption, etc.
While this may not be ideal and precise, when dealing with fat soluble vitamins and their absorption rate according to how much fat is present, there is simply a lack of data and numbers to draw better conclusions, and it has not been figured out precisely what the perfect equation for absorption would be.

There are diminishing returns when a nutrient surpasses their optimal range per 100 kcal, as it is less important to eat more of it the more you already have. Everything is based on eating 100 kcal of the food, but the optimal threshold--after which there are diminishing returns--is based on 700 kcal meaning you would get 100% of what the staple has to offer, as at least 700 kcal/day of eating main staples is usually reasonable (roughly a third of the daily calories).
NOTE: you can and will get these nutrients when eating other foods throughout the day, too. It is not required that a staple be in optimal range for it to be good enough, a staple being in optimal range of a nutrient merely means it is exceptionally good when it comes to such nutrient, and it covers the entirety of the day for the RDA of the nutrient with 700 kcal, thus not having to worry about the nutrient with other foods if eating enough of the staple.

Finally, a negative value is placed when a food is too low in caloric density, to the point where you would have to eat enormous volumes of it for the same amount of calories as other staples that would be much denser. A negative value is placed after a certain threshold (150g/100 kcal), because it is impractical to eat high calories of a certain staple (e.g. you would have to eat 667g of squash for 100 kcal, but only 41g of oat bran for 100 kcal, so they cannot be considered as efficient/practical to eat just being compared on the nutrient density per kcal).

It is important to note that you can prioritize a certain nutrient more or less according to what you are missing, if with a personalized diet plan you are struggling to meet the RDA of a certain nutrient--in which case, the Final Value of Nutrient Density / kcal would not represent what is best for your specific case, and you can instead sort for the nutrient of most interest.