What food is the healthiest?
The answer to what food is the healthiest is both simple and complicated at the same time. There are many influencing factors in the human body, making it complex. The simplicity is that almost whatever one think is the most important mechanism between food and well-being, vegetables turn out to be the answer. Want to eat more minerals, vitamins or fiber; vegetables have more nutrients per calorie than any other food group (bottomuphealth.net/nutrition-comparison). Want to eat more antioxidants; after spices, herbs and berries, vegetables have most (Carlsen et al, 2010). Want to eat less calories; vegetables have least. Want to have good metabolites from the bacteria in the colon; vegetables are likely to give most beneficial metabolites (den Besten et al, 2013), per calorie of food. Therefore, at the end of this article there is a tip of the easiest way to add more vegetables to the diet, but keep reading to get information that you might not find elsewhere.
The shift in diets from hunter-gatherers with plenty of vegetables, tubers, berries, wild meat and seafood to plenty of processed grain products has reduced our nutrition, especially of potassium and fiber, to suboptimal amounts (Makki et al, 2018; Sebastian et al, 2006; Yang et al, 2011). Reversing back to more vegetables as well as tubers, legumes, fruits, berries, nuts and seeds restore the nutrient intake to more favorable amounts. Below is some information about the crucial impact of potassium and fiber, two of the most fundamental nutrients, for health and physical and mental performance, which further explains the benefits of vegetables, fruits and potatoes.
On the importance of potassium
Human cells have gradients of potassium ions and sodium ions, called electrolytes, which give rise to an electrical potential over the cell membranes. These gradients give the cells control of the flow of water, pH and nutrients, as well as functions for electrical nerve signals and muscle contractions. The main work is done by the ubiquitous sodium-potassium pump (also called Na+-K+-ATPase) that lifts two potassium ions in and three sodium ions out of the cells, for every ATP energy unit used. This makes sure that the potassium level is high and the sodium level is low inside the cells, but the other way around outside the cells. Maybe 20 % of the body’s energy usage, goes to uphold and restore these gradients (Rolfe and Brown, 1997), that’s how important they are, especially for the function of the muscles and brain.
Obviously, the body needs to balance the levels of potassium and sodium. The cells, the kidney and the intestine have mechanisms to regulate varying food intakes, but it’s favorable for the cardiovascular system, the brain, the muscles and the bones to have a high intake of potassium and a medium to low intake of sodium (Haddy et al, 2006; Kong et al, 2017; Sun et al, 2017; Yang et al, 2011). Potassium’s long term prevention of calcification and stiffening of the arteries is of outmost importance, since all the body is dependent on efficient blood flows. When the brain or muscles work, potassium flows out of those cells and has to be pumped right back in, to be reused. Some of the potassium leaks away and dilate the blood vessels in the surrounding area, which increases the blood flow to the area of action (Wilson et al, 1994). Potassium contributes to the brain and the muscles performance, both through its direct function in the nerves and the muscles and in its increase of the blood flow. The positive effects of potassium on the blood flow, the blood pressure, the blood vessel function and the bones, might be one of the reasons that physical exercise is healthy, when it causes a systemic increase of potassium.
To keep the potassium level within the cells high, a high intake through food or supplementation is needed. Potassium content in food is as follows: Vegetables, potato and some fruits are richest in potassium, per calorie (bottomuphealth.net/nutrition-comparison). Yoghurt, milk and legumes contain medium to high amounts of potassium. Meat products have medium to low potassium content. Whole grains contain rather little potassium. Refined grains have almost no potassium. Therefore, you should eat vegetables, fruits and potatoes to fill up your potassium, for the sake of the brain, the muscles, the cardiovascular system and the bones.
On the importance of fiber
Since humans don’t digest fiber, but leave it for the symbiotic bacteria to digest, it might be surprising that fiber has a rather big effect on health (Anderson et al, 2009). One reason is that those bacteria produce important substances for us, such as the short chain fatty acids (SCFAs) acetate, propionate and butyrate, as well as other beneficial or essential substances. The amount of SCFAs produced is higher from dietary fiber and resistant starch than from other food components (den Besten et al, 2013). SCFAs have beneficial effects on the colonocytes (epithelial cells of the colon (large intestine)), so that they use up the oxygen and produce more mucus in the colon (Koh et al, 2016), which prevent bacteria from irritating or breaking the integrity of the colon, which otherwise might cause inflammation. In case the butyrate producing bacteria diminish, the colonocytes lose some oxygen consuming ability and produce more nitrate. The increased oxygen level in the colon suppresses beneficial anaerobic butyrate producing bacteria further and give chance to pathogenic E.Coli and Salmonella to grow (Byndloss et al, 2017). Unfortunately, this negative microbiota can arise from excessive antibiotic use.
The SCFAs also enters the body, where they have beneficial effects on several organs, such as better regulation of the immune system, increased insulin sensitivity, more satiety, reduced fat storing activity and lower cholesterol and free fatty acids (den Besten et al, 2013). With all these positive effects coming from the SCFAs, it shouldn’t be surprising that fiber has a huge impact on health. It also explains why eating some vinegar could have health benefits, as it contains acetic acid that is an SCFA.
Another big benefit from eating plenty of fiber is that fiber makes the stomach full with less calories, which reduces the risk of overeating. Longevity is associated with calorie restriction (Guarente and Picard, 2005), while overeating increases the risk of overweight and metabolic troubles.
Fiber content in food is as follows: Vegetables, legumes, berries and some fruits have most fiber per calorie (bottomuphealth.net/nutrition-comparison). Potato, sweet potato and whole grains contain medium amounts of fiber per calorie. Refined grain products, for instance white flour and white rice, are low in fiber and other nutrients and are therefore easy to overeat.
Reducing sugary products, refined grains, some added fats and other energy dense food products, is also important steps for weight control and to steer the diet towards the nutrient rich unprocessed foods.
How to eat more vegetables, effortlessly
The quickest way to add more vegetables to the diet is to fill a bowl/deep plate with frozen vegetables, fill up with water and microwave for 5-10 minutes, until boiling. If more softness is desired, the vegetables can be left in the hot water for some additional time outside the microwave, followed by draining or rinsing in cold water. Seasoning with herbs, spices, lime, vinegar, oil, cheese, avocado, meat or whatever, after own preferences, makes it taste well too. One or two plates of this, or other vegetables, per day, makes good for the body and mind.
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References:
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