Proper diver nutrition involves adequate intake of protein, fat, carbohydrate and fiber. Protein, an important component in body functioning, can be found in meat, vegetables, grains and potatoes. Fat, essential for warmth, buoyancy and cushioning heavy gear, is readily available in the modern diet.
A diver eats an evening meal of steak or burgers, potatoes mashed with butter and milk and a small side of buttered vegetables. For dessert there’s coffee with cream and sugar and ice cream and/or cake. A good dinner of protein for muscles, calcium for bones and energy for diving? No. Not by far. When the U.S. Department of Agriculture surveyed American dietary habits it found many Americans who think they eat healthily don’t at all. The sample dinner is typical of three times too much fat, saturated fat and cholesterol, double the needed protein, too much simple sugar and too little fiber, vitamins, complex carbohydrates and water. This kind of eating is increasingly associated with heart and vascular disease, vitamin deficiency, dehydration; calcium loss, being overweight, having high blood pressure and some cancers.
What Is Eating Right?
Eating right does not mean giving up every food you love and eating only things you hate. Eating right involves good food, regular meals, better health and better diving health. Good meals need no secret energy foods and, with few exceptions, no special supplements.
This article looks at two main nutritional components – protein and fat. Next month we’ll cover another two major nutritional components – carbohydrate and fiber. In both issues we’ll explain why you need them, which foods have these components, problems with getting too much of them and how much is enough. With simple, good tasting modifications of bad habits, good eating can become an easy habit to improve health and well-being.
WHY YOU NEED PROTEIN: Just about every function of the cells in your body involves protein. Protein is made of chains of small molecules called amino acids. Amino acids link to form all the different proteins. Plants can make all the amino acids they need to produce proteins. That’s why a plant does not need to ingest protein to survive. Of the 20 or so amino acids you need to make protein, the adult human body can make all but about eight. You must eat the eight you can’t make. These eight are called essential amino acids.
WHERE TO GET PROTEIN: People often think of meat when they think of protein. Many are surprised to find that vegetables are good protein sources. It used to be commonly stated that plant protein – often called incomplete protein – was not quality protein. Incomplete was thought to mean that plants do not contain all eight of the essential amino acids and, therefore, you could not make the protein you need from them. However, plants have all eight essential amino acids. They often have less of one or two of the essential amino acids compared to quantities of the other six or seven. However, all eight are usually present in varying degree.
In the past it was commonly stated that vegetables low in one essential amino acid had to be carefully combined with a different vegetable high in that amino acid to “complement” the protein and arrive at a mix with all essential amino acids. Rice and beans are a well-known good mix providing complete protein. However, carefully combining vegetable foods is not necessary in the average Western diet, which contains more than enough amino acids of all kinds from all the various foods.
Grains, potatoes and vegetables make good main dishes. Unlike meat, vegetables have protein, fiber and vitamins, with no cholesterol and little fat. Vegetables also do not have the hormones and antibiotics given to livestock that commonly remain in meat. Plants produce all eight of the essential amino acids you need, which means you can get all the protein you need, even for heavy activity, from eating vegetables. With a few new recipes you can make vegetables into healthy, good tasting main dishes.
DON’T OVERDO: Human protein need is not high. Deficiency is rare in modern Western diets. Average daily protein intake by adult Americans is usually two to four times higher than that recommended by the National Academy of Sciences. Extra protein is not stored and does not become extra muscle. It goes several routes. One is through your excretory system, taking water with it to produce urea. Dehydration can result, reducing endurance capacity, increasing risk of heat illness and possibly contributing to decompression sickness. Another exit route for excess protein is conversion to fat. It can’t be turned back to protein later. High animal protein diets, common with too much meat, dairy and protein supplements, have been shown in studies to increase bone calcium loss through the urine. High protein diets have been associated with increased risk of certain cancers and heart disease.
Some people eat too much protein, believing there are benefits that outweigh the problems. Eating extra protein does not cause your body to enhance its activities that use protein. Although normal cell reactions that build muscle use protein, extra protein doesn’t build extra muscle, any more than it increases other reactions using protein. Protein is used to produce skin pigment, enzymes, hormones, antibodies, skin and bone, as just a few examples. Eating more protein does not turn you brown or grow more skin or bone. For building muscle, your body can only use so much protein and no more, regardless of the amount of exercise. Past that amount extra protein may harm.
HOW MUCH IS ENOUGH? Depending on your body weight, only 12 to 16 percent of your daily calories need to be from protein. For perspective, oatmeal has 17 percent protein and peas have 26 percent of their calories as protein. The National Academy of Sciences recommends a range of 0.8 to 1.6 grams per kilogram of body weight, averaging only one gram of protein for each kilogram you weigh. Protein needs of a 120 pound (54.5 kg) diver are close to 55 grams a day. A 150 pound (68 kg) diver needs about 68 grams. A 180 pound (81.8 kg) diver needs about 82 grams. As a rule of thumb, if you eat enough to maintain your weight, you eat enough protein.
WHY YOU NEED FAT: Having a certain amount of fat on your body is essential to life and handy to divers, up to a point, for warmth, buoyancy and cushioning heavy gear.
You burn fat 24 hours a day, while awake and asleep, for the energy you need to stay alive. Burning fat is part of what is called aerobic metabolism. The word aerobic means you are using oxygen. You breathe to supply the oxygen your body uses to burn fat as fuel. This process of aerobic metabolism is often confused with the concept of aerobic exercise. With aerobic metabolism you use your aerobic system of making energy from fat all the time – sleeping, sitting in a chair, right now while reading. That’s why you breathe all the time. When you begin activity suddenly or exercise at too high an intensity to supply all your energy demands with the slow system of fat burning, your body temporarily switches over to burning mostly stored carbohydrate without using oxygen, in processes called anaerobic metabolism.
Your carbohydrate stores are limited. When you work at so high an intensity that you switch to mostly anaerobic processes, you soon exhaust your stored energy. You need to slow to a pace where your aerobic metabolism can match energy production to the demand. Then you switch back to mostly burning fat. You burn more fat when you exercise at moderate aerobic exercise intensity than when you just sit and breathe.
WHERE TO GET FAT: Eating fat is a good way to wind up with fat on your body. Your body is very good at making sure fat, so important to survival, gets stockpiled. You get the building blocks that your body uses to make fat from the fat you eat and from eating extra carbohydrate and protein. Keep two facts in mind about dietary fat: Although stored body fat is a major fuel, eating fat does not give you more energy and you do not have to eat fat to supply it. Your body is very good at making its own fat, sometimes, plenty of it, from most of the things you eat.
Many foods common in the modern diet are high fat. Most fast food, candy, dessert and packaged snack foods have unhealthy fat amounts. Meat, even lean cut, is usually above the American Heart Association’s recommended fat maximum of 30 percent. Bacon averages 80 to 90 percent fat, bologna sausage is 83, hot dogs 79, lamb chops 74, pork chops 72 – even before you fry them – and ground beef 62. Cutting back on these will reduce your daily fat intake. Dairy products, except skim milk products, are high fat. Milk labeled 2 percent fat is not 2 percent fat. It is 35 percent fat. The 2 percent figure is clever labeling. Milk labeled whole milk, or 3 percent fat, is 48. Skim milk, called 1 percent, has 23 percent of the total calories as fat and nonfat milk is 5 percent fat.
DON’T OVERDO: Your body breaks down dietary fat to simpler compounds for energy. Your body rebuilds any excess into fat, storing it ambitiously for later use in special cells making up your adipose tissue. Your body also helpfully rebuilds breakdown products of excess carbohydrate and protein into fat. Even if you ate no fat at all, by eating more calories than you burn every day you will gain fat.
HOW MUCH IS ENOUGH? Keep fat as small as part of your total calories as you can, with most of that vegetable fat. The American Heart Association recommends no more than 30 percent of total calories should come from fat, in contrast to the average Western diet that averages more than 40 percent and higher. Pritikin diets, successful in slowing, and in some cases reversing, heart disease, try to keep to 10 percent fat.
Exercise Of The Month
No exercise is right for every diver. As with any new exercise, see your physician first.
Sitting Exercises: Sometimes you get stuck sitting for long periods in meetings, classes, driving or double features, where there is no opportunity to get up and stretch to relieve tight muscles and cramped postures. When possible, make an excuse to stop and get up to stretch and walk around. If impossible, try these few simple chair exercises every 15 to 20 minutes:
* Alternately tighten and relax your leg and backside muscles. Then do the same with your arm muscles.
* Bend and flex your ankles.
* Alternately tighten your hands into fists, straighten them out as far as they will go, then relax.
* Roll your shoulders forward and back slowly, together and one at a time.
* Your neck bones were not made to roll your head around – over time it may cause early wear. For neck range of motion tip your head forward and back, side to side, each ear to shoulder.
* Breathe in and out deeply one or two times.
* Open your eyes wide.
* If you do not have a back condition that prevents it, push your shoulders back hard against the seat of your chair, allowing your back to arch, then relax.