My Thoughts on Umami - by Tilak Nagodawithana, Ph.D.

I once met an elderly lady in the grocery store who was looking for the “no MSG” printed on the soup label to make sure she was not buying the product which everyone tells her is nutritionally unhealthy. I inquired if she had any reaction to consuming MSG-containing foods such as tomato, cheese, mushroom, meat, fish or Chinese food and the answer was negative. If this compound is facing so much negative publicity, let us see why it is so, considering the fact that this organic compound is present in almost all foods we consume.

MSG is the sodium salt of glutamic acid which is the most abundant amino acid in all proteins. Japanese found early on (Ikeda in 1908) that the active ingredient in sea tangle, which they used extensively to enhance the savoriness in soup is the sodium salt of glutamic acid. In the 1960s, Kuninaka found that in human taste sensation, there exist a remarkable synergy between glutamate (MSG) and 5’-nucleotides (5’-IMP and 5’-GMP) present in mushroom and bonito. Today, these three products which enhance the flavor and brothiness of less savory products are referred to as umami compounds. Although there has been great deal of studies conducted on the properties of these three compounds, the mechanism by which it enhances savory flavor is not worked out yet.

However, extensive studies have revealed that the receptor sites for these three umami compounds are different from the receptor sites related to primary taste stimuli, namely, sweet, sour, salty and bitter. Because of this unique nature, it is now considered as the fifth basic taste.

During evolution, why did living forms develop specific receptors for sweet, sour, salty, bitter, and umami in the oral cavity? A simple explanation is to address nutritional problems and promote sustenance. For example, sweet receptors can detect much needed calorie foods; Salt receptors can provide Na ions to maintain sodium balance; Bitter perception can help avoid poisonous material; avoidance of excess sour compound to prevent tissue damage; and Umami receptors for living things to get attracted to the much needed proteins and amino acids for synthesis of enzymes and other nitrogenous compounds to maintain the biological functions. If Glutamate (MSG), which is a key Umami compound, is totally avoided from our food, which in essence is a way to completely avoid consumption of the much needed protein, the consequences can be disastrous. If that had been the case in evolution, the elderly lady I met in the grocery store may not have been there to read the label, in the first place.

How To Get Enough Calcium

Everybody needs Calcium, right? If you aren’t getting enough in your diet, just drink some milk or take a supplement, right? Wrong!

First off: If you are eating even close to a balanced diet, you’re getting plenty of calcium. It’s everywhere and in all kinds of foods – dairy, of course – but also in green vegetables, fish, nuts and fruit.

Here’s the gem: Calcium uptake isn’t a function of how much extra calcium you ingest. It is a function of how much muscle mass you have. It makes perfect sense: When you build muscle mass, your body says “I’d better strengthen my bones to support these muscles”. You release chemicals that signal for the absorption of more calcium.

The lesson: Take all the supplements you want. Unless you start moving around – or, better yet, lift some weights, they’ll do you no good at all. Stop mega-dosing. The best way to avoid osteoporosis is a diet rich in calcium and regular light weight lifting.

Calories in. Calories out.

Like Scotty says on Star Trek, “I can’t change the laws of physics!” He’s right, and you can’t either.

A ‘calorie’ is a measure of the ‘work’ done. In physics, Work = Force x Distance. Here on earth (because of gravity), you can pretty much equate “Force” with “Weight”. So a calorie will move a certain amount of weight (like your body, or a dumbbell) a certain distance (like a mile, or from the floor to over your head).

All foods provide calories that we use to perform work (i.e. move weight over a distance). Carbohydrates and Proteins provide about the same amount: 4 calories per gram. Fats provide more: 9 calories/gram. (An easy way to calculate the calories in a food is to remember “PFC 494”. To calculate calories, add the grams of Protein x 4, Fat x 9 and Carbs x 4.)

Even though all foods can be used for calories, they can be used for other things too - and they get converted into calories in different ways.
· Carbs are only used to generate calories.
· Proteins provide the building blocks for life: to create muscle, tissue, organs, bones, nerves, etc. Your body will also burn proteins (to make calories) if there aren’t any carbs around or if it has extra proteins, but that’s kind of like burning the furniture to heat the house. It’s your body’s last choice.
· Fat stores calories. Your body can get calories directly from the fats you eat – or from the fat you have saved up all around your body.

Calories in = Calories out. Always. That’s just the way it is (back to the laws of physics.) A calorie, is a calorie, is a calorie: Calories are all the same – regardless of where they come from or when you eat them – and there is only one way to get rid of them: by doing work! If you eat too many, your body stores them as fat. If you don’t eat enough, your body will get the calories it needs from stored fat.

Dieting, although not easy, is simple: If you use more calories (by moving weight over a distance) than you take in as food, you lose weight. Period. Simple.

Myths about calories:
· Myth #1: Eating before bed-time will make you fat. It won’t - any more than eating at any other time of the day. The laws of physics on this (Work=Force x Distance) make no mention of “time of day”.
· Myth #2: It matters how fast I run or how long I work out. Actually, it doesn’t matter. There is no mention of ‘time’ or ‘speed’ in the calorie equation either – so, interestingly, the number of calories your burn has nothing to do with how long or how fast exercise. It’s all about the weight and distance. In other words, running a mile burns as many calories as walking a mile. Or, when burning calories with weights, the amount of weight matters and the number of reps matter – but how fast you do it doesn’t matter. Of course, you cover more distance if you run fast, but it takes less time – so they cancel each other out.
· Myth #3: Calories from fat are bad. No, they are the same as all other calories. Fat just has a lot of them in it.

Fun Facts:

• Other familiar terms that measure “calories” include Watts, B.T.U’s, Horse Power, Joules, Foot-lbs, etc.
• There is ONE other way to burn calories: By creating HEAT. So  - do you burn more calories in the winter? Yes! But, compared to the calories you expend doing work (part of which creates heat too), they are nearly insignificant - and pretty constant except when you are moving.