Richmond: While people usually think of turkey or ham first during a holiday meal, there are a few things that can help balance out your plate. Colorful vegetables like green beans, collard greens, roasted carrots and mashed sweet potatoes are rich in important micronutrients. But how you prepare them will help determine whether you get the most nutritional value from each meal this holiday season.
As a biochemist, I know that food is composed of many chemical substances that are important to human development and function. These chemical substances are called nutrients and can be divided into macronutrients such as carbohydrates, fats and proteins and micronutrients such as vitamins and minerals. Vegetables are rich in micronutrients that the human body needs to metabolize – or convert food into energy – as well as build and maintain cells and tissues. These micronutrients can be classified into three types: minerals, water-soluble vitamins, and fat-soluble vitamins. The greens on your table – collard greens, kale, spinach, green beans – are rich sources of magnesium and calcium.
Your body needs these two key minerals for muscle movement and bone health. Magnesium is essential for many enzymes that play an important role in DNA synthesis and repair as well as protein production and metabolic function. Cellular processes, especially precise DNA synthesis, are important in protecting your body from diseases like cancer. Calcium helps regulate the pH in your body, affects your metabolism and strengthens your nerve impulses. Nerve impulses are important for your senses and your memory.
Greens are also a source of iron – you were right, Popeye! – which is especially important for hemoglobin and myoglobin, the oxygen-binding proteins that transport and store oxygen in your body, respectively. In addition, the human body needs iron for processes that help generate energy, protect against oxidative damage, and create hormones. Orange vegetables – carrots, pumpkins, sweet potatoes and squash – also contain some levels of calcium and iron as well as high levels of potassium. Potassium is important for maintaining muscle movement, nerve impulses and low blood pressure. Although it is not a colorful vegetable, white potatoes also have very high potassium levels.
Most green and orange vegetables contain high levels of vitamin C. Vitamin C is an important water-soluble vitamin because it acts as an antioxidant. Antioxidants protect your cells from certain types of damage caused by highly reactive molecules known as free radicals. Additionally, vitamin C can enhance the immune response and is essential for the synthesis of collagen, the major protein in your skin.
Although taking too much vitamin C will never make you sick, healthy amounts of it can help keep your skin soft, help prevent diseases like scurvy, and potentially shorten the duration of colds. Can. A plate of white potatoes contains high levels of vitamin B6, a component of enzymes essential for carbohydrate, fat and protein metabolism. It also helps form healthy blood cells and is important in the production of neurotransmitters like serotonin and dopamine, which regulate pleasure and enjoyment.
One of the most important vitamins you get from green vegetables, especially leafy vegetables like kale, spinach, collards and Brussels sprouts, is vitamin K. Vitamin K is an essential component of enzymes that make proteins in bones and proteins that help stop bleeding after injury. Vitamin A is another important fat-soluble vitamin found in spinach and orange vegetables. The source of vitamin A in vegetables is actually beta carotene, which breaks down into two molecules of active vitamin A after consumption.
Vitamin A is essential for vision as well as cell differentiation, reproduction, bone health and immune system function. Consuming micronutrient-rich vegetables is very important, but equally important is your body’s ability to absorb nutrients and deliver them to the cells that need them. Macronutrients like carbohydrates, fats and proteins that mainly make up the food we eat are absorbed very efficiently into your bloodstream. However, only 3%-10% of some micronutrients are actually distributed throughout your body. Other ingredients and factors in your food can control your ability to absorb vitamins and minerals.
Therefore, it is important to prepare vegetables in a way that enhances the body’s ability to absorb their essential vitamins and minerals. A good example of this is iron – specifically, iron in the food you eat. Heme iron comes only from animal products and is most easily absorbed. On the other hand, plant-based iron in green and orange vegetables is non-heme iron, which your body can’t easily absorb. Consuming vitamin C with vegetables can increase the amount of nonheme iron. So, squeezing the juice of a lemon or orange can not only enhance the taste of your vegetables but also increase the micronutrients they provide.
Fat-soluble vitamins, such as vitamin K and vitamin A, are best absorbed when the food contains some fat, which you can get from oil. This is especially important for vitamin K because green vegetables are its primary dietary source. This is in contrast to the other minerals and vitamins discussed which can also be obtained from animals or legumes which already contain some amount of dietary fat. After intake, vitamin K must be packaged with other fats in structures called micelles or lipoproteins that can circulate in the bloodstream. This means it’s a good idea to dress your greens with some source of fat – olive oil, avocado oil, butter or even a little bacon grease.
So, if you’re looking at collard greens on your plate and wondering if they’re as healthy as eating raw greens, think about it in terms of biochemistry. While raw green vegetables provide you with plenty of fiber and minerals, they won’t help your vitamin K levels the way green vegetables cooked in oil will. Enjoy your time at the holiday dinner table. Fill your plate with everything you want to eat, and make sure it’s not completely fat-free to help your body process and utilize all the micronutrients.