|My favourite paradigm shift cartoon|
The field of nutrition science suffers from the absence of a unifying hypothesis on which to build a dietary strategy for prevention; there is no Kuhnian paradigm, which some researchers believe to be a prerequisite for progress in any scientific discipline. An understanding of human evolutionary experience and its relevance to contemporary nutritional requirements may address this critical deficiency.So, we're all pretty much in the dark, to some extent, something that is surely reflected in the plethora of claims for various wonderdiets. Here's some more from another paper, which reinforces what I've already come to believe about my wheaty food intolerance - me genome just couldn't keep up...
There is growing awareness that the profound changes in the environment (eg, in diet and other lifestyle conditions) that began with the introduction of agriculture and animal husbandry ≈10000 y ago occurred too recently on an evolutionary time scale for the human genome to adjust ... The evolutionary collision of our ancient genome with the nutritional qualities of recently introduced foods may underlie many of the chronic diseases of Western civilization.As part of the course, I've started a food diary using MyPlate and have calculated my Body Mass Index (BMI) showing that I've a little way to go if I don't want heart disease, a stroke or type 2 diabetes...
Losing 19.3 kilos puts me in the middle of the healthy weight range. This is confirmed by my waist measurement, which puts me as an apple shape, and so at increased risk of developing type 2 diabetes and cardiovascular disease. Bugger.
My estimated Basal Metabolic Rate (BMR) is 1929 kcal/day +/- 167 kcal, which means that a rough estimate of the number of calories required per day based on my current activity level is: 3279 kcal/day. 500 less than this will help me lose around 1lb per week.
Aside from my impending doom, my main learning today has been about macro- and micro-nutrients. I found a fabulous image that sums it up, as well as a whole blog post at Healthy Annie's which I have re-posted here (original at https://healthyannie.wordpress.com/2012/03/08/nutrients-micro-and-macro/):
Macronutrients: our fuel. They are the only nutrients that provide energy and they are needed in relatively large amounts to support normal function and health. Energy is measured in calories. One gram of carbohydrate gives us 4 calories, as does one gram of protein. One gram of fat, however, gives us 9 calories. So for every gram of fat we consume, we get more than two times the energy than from a gram of carbohydrate or protein. The body prefers carbs for its primary energy source. If there isn’t enough glucose, our bodies go into ketoacidosis (hello there, Atkins diet fans, that’s you!). Fat is used when we are at rest and during low intensity exercise. Carbohydrates are used more during intense exercise. According to the Institute of Medicine’s AMDR (Acceptable Macronutrient Distribution Range):
- 45-65% of your energy should come from carbohydrates
- 20-35% of your energy should come from fats
- 10-35% of your energy should come from protein
- Vitamins are compounds that contain carbon and regulate many of our body’s processes. Many of them have been extensively tested and shown to improve certain functions of our body and/or to reduce risk for certain diseases or other health issues. I cover vitamins individually in this blog; and as of this writing, so far I have already blogged about vitamin A. More to come!
- fat-soluble vitamins are ones that the body can store for a while and therefore we don’t have to consume every day
- water-soluble vitamins we need to make sure we consume daily because the body can’t store them (except for b12)
- Minerals are naturally occurring substances that do not contain carbon. They cannot be digested further or broken down anymore; they are elements. Minerals come from the environment and are never synthesized in a lab or by a plant or animal.
- major minerals are ones that we need to consume at least 100mg of per day. Maybe I will make a post about them later.
- trace minerals are ones we don’t have to consume much of (less than 100mg/day).
Thompson, Janice & Manore, Melinda. Nutrition: An Applied Approach, 3rd Ed. Copyright (c) 2012 Pearson Education, Inc.