WHAT SHOULD I EAT? – MOSTLY PLANTS. part 1
~~~~~~We are here ↑
This article is the first on our series delving into the specifics of the base physiological needs of Maslow’s hierarchy (above image, bottom row), and the long term importance of not just meeting those needs, but finding your nourishment. We are starting with food. Food is a massive topic, which will span several articles. We will be discussing the foundation of food as nourishment in this first article. In subsequent articles we will be expanding on topics such as food inequity and food deserts, diet culture, ethics, ecological impacts, ancestry, soil degradation, pesticide and herbicide use. There is A LOT to talk about.
Let’s start with the basics. Food is composed of:
Macronutrients: carbohydrates, proteins, fats, fibre (“counting your macros” in diet jargon)
Micronutrients: vitamins, minerals
Phytochemicals (phyto- meaning plant) like beta carotene in carrots, curcumin in turmeric
In both the macronutrients and micronutrients, there are essential and non-essential nutrients. Essential means that we must get the nutrients from our diet: our body cannot make them. Phytochemicals are produced only by plants, not by our bodies, so are therefore not considered “essential”. Conventional medicine does not consider phytochemicals as necessary or important parts of the diet, but it is important to note that research into the utility and importance of phytochemicals is increasing. Watch this space.
Most of us need nutrients to fuel our body processes. I will save a discussion of breatharians for another time. (Breatharians are people who don’t eat food at all and get all their requirements from air.)
We must consider the nutrients that are actually in the food we are eating (which also depends strongly on the health of the soil!), but more importantly, we need to consider what nutrients our body will actually absorb and be able to use (digestion, absorption, assimilation). You are not what you eat, but what your body can actually absorb and use.
So, humans need a combination of carbohydrates, proteins, fats, fibre, and micronutrients, and, I would argue, phytochemicals. Our bodies can store many nutrients so we don’t need all the nutrients, all the time. There are guidelines such as the HHS/USDA Dietary Guidelines which attempt to provide folks with an answer to the question: What should I eat? These guidelines are usually what conventional medical doctors use to make recommendations to patients. The guidelines have been criticised for being white-centric and racist, fat-phobic, and heavily influenced by the multibillion dollar food industry who funds and manipulates much of the research. Yep. Read this article by Dr. Mark Hyman for more about how low fat diets are no longer recommended and were stealthily removed from the guidelines, so as not to create a ruckass and decrease the sale of anti-cholesterol medication (statins). The guidelines also place an emphasis on calorie reduction. Calories are the energy-generating potential of macronutrients. The USDA guidelines say that the estimated calorie needs for an adult are 2000-3000 a day. Consuming that number of calories, or fewer, a day does not mean you are “healthy” or nourished, and reducing calories may or may not result in fat loss. You will likely not find the information you need to be nourished in government-produced dietary guidelines.
Humans have anatomical and physiological features of an omnivore- an animal which eats plants and animals. Dietary flexibility is a hallmark of the adaptability of humans. We are not koalas or pandas, restricted to predominantly one foodstuff.
For example, the Innuit people and Okinawan people have very different traditional diets. They have the same essential anatomy- the same type of teeth, stomach, intestines, but very different intestinal microbiota (organisms) and different adaptive physiology (the way their bodies use nutrients). They are adapted to their diets. Some of this is genetic (inherited changes in the DNA), some is epigenetic (inherited and environmental influences on the DNA), and some is purely influenced by the environment. And they, like any other human, can re-adapt to different diets, at least to an extent.
what should we eat?
The vast majority of our dietary needs can be met by plants, as well as fungi like mushrooms- which are not technically plants. (Side note: I highly recommend the film “Fantastic Fungi”)
“The vast majority of your diet should be plants (and some fungi).”
The vast majority of nutrient needs can be met by eating a variety of fresh, good quality plants (and fungi). There are 4 critical nutrients which are found predominantly in animal products: vitamin B12 (cobalamin), vitamin D, iron, and EPA and DHA omega-3 fatty acids. Farming, fishing, and aquaculture are ethically questionable and environmentally damaging. Eating meat, fish, and eggs may or may not be nourishing for your particular body, but the quantity and source of the animal products you consume most definitely deserves inquiry.
what about plant (or fungal) sources for these nutrients?
There are plant and/or fungal sources for these 4 critical nutrients, but they are often in lower concentrations and may not be as available for the body to absorb as the animal-derived nutrients. Some foods like cereals and milk/mylks may be fortified with these nutrients to try to fill the gaps- i.e., they are added by the company during manufacturing. The fortified form may not be shelf-stable (like in cereals) or as bioavailable (available for your body to absorb) as they are actually in food.
Vitamin B12 is critical for the brain, nerves, and red blood cells. Vitamin B12 can be found in algae like nori, chlorella, spirulina, as well as tempeh (fermented soy beans), and nutritional yeast. Plant-derived vitamin B12 may be more in the form of “pseudovitamin B12” which is not available for the body to use. It can depend on the formulation. Here’s a journal article which discusses this.
Vitamin D is important for bone and muscle health. Vitamin D can be absorbed from the sun through the skin, and is also found in mushrooms. Mushrooms need to have some exposure to sunlight or UV light to contain vitamin D, so commercially-grown mushrooms grown completely in the dark have very low vitamin D levels. Here’s a journal article which discusses this. You can cut up and place commercially grown mushrooms in the sun for a couple of days, gills exposed, to increase the vitamin D content. Here’s a Huffpost article which discusses this.
Iron is an essential mineral, critical for ability of red blood cells to carry oxygen, and also important for muscles. The form of iron in plants (known as non-haeme iron) is poorly absorbed compared to the iron in meat (haeme iron). Legumes, especially soybeans, and dark green leafy vegetables are some of the richer sources of non-haeme iron. It can be difficult for the body to absorb non-haeme iron because it can be bound by plant components like phytates and tannins. Eating foods rich in vitamin C at the same time as non-haeme iron sources will improve the absorption of non-haeme iron. Vitamin C-rich foods include dark green leafy vegetables (hoorah!), bell peppers/capsicums, citrus of course, papaya, kiwi fruit, strawberries, broccoli, Brussels sprouts. Here’s a journal article talking more about iron.
Omega-3 fatty acids are important fats for reducing inflammation. Most important are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). The main plant source is microalgae. Here’s a journal article talking more about plant sources of EPA and DHA.
There are omega-3 fatty acids in plant sources like sunflower seeds, walnuts and flaxseeds but the omega-3s are mainly in the form of ALA (alpha-linoleic acid). Humans cannot convert ALA (a precursor fatty acid) to DHA and EPA particularly well (unlike some other animals), and though ALA is also a beneficial fatty acid in its own right, DHA and EPA are the most crucial for anti-inflammatory effects and brain health. Here’s a journal article talking about omega-3s.
Eating mostly plants (and some fungi) is going to provide you with the most nourishment. “Plant-based” is not just a hype or fad. If you do not consume animal products, then you can benefit from adding in the alternative whole food sources described above, or taking high quality supplements.