|Last update November 11, 2021, article reviewed & updated multiple times since September 8, 2001.|
What You Need to Know
In our last three discussions about protein:
- Protein and Amino Acids
- Protein Digestion and Protein Absorption
- Excess Protein Turns Into Carbohydrates In The Body
we have learned that protein is made of carbon, hydrogen, and oxygen with the addition of the key ingredient nitrogen. We have learned that nitrogen is essential for life, and that the body breaks protein into amino acids in order to get the nitrogen. The amino acids are rebuilt into proteins for the repair and growth of the body, since the protein parts of all our tissues are being destroyed continually, and need to be replaced continually.
We looked at the fact that growth involves more protein construction than protein destruction, and that it leads to an increase in living tissue. In children, most amino acids are used up in the building and developing functions, with only small amounts becoming waste products. Consequently, the diet of a child should nearly always be higher in protein than the diet of an adult.
We discussed that each tissue selects what it needs from the “buffet” of amino acids that circulate in the blood, as amino acids constitute the form in which protein is presented to the tissues, just as glucose constitutes the form in which carbohydrate is presented. We learned that the liver removes and recombines nitrogen in a process called deamination so that amino acids can function. And, then came the unwelcome news that the deamination process leaves behind … carbohydrates.
Protein Converts To Carbohydrates!
As I pointed out last time, the liver converts an average of 58% of the protein we eat into carbohydrates, and that the carbohydrates-from-protein are handled by the body just like “regular” carbohydrates. It is broken down into glucose by the simple water-related steps of hydrolysis; it is used for fuel to run the body; it is converted to glycogen and stored. If there is too much of it, it is converted into body fat.
Remember, it is only the actual protein portion of protein food that becomes carbohydrate. Much of protein food is water or fat, or even undigestible parts that don’t enter into this discussion. And, of course, some protein foods have a regular carbohydrate portion, such as the carbohydrates in cheese and eggs.
This is how you can ‘guesstimate’ how much of the protein-food you eat will become sugar: in every ounce (by weight) of protein-food, there are about 6 grams of actual protein. Of that 6 grams, about 58% can become carbohydrate. This means that of every ounce of protein food you eat, your liver can create about 3.5 grams of sugar. This is THE major source of Hidden Carbohydrates.
There is some good news, however, but it comes with some more bad news. The good news is that insulin tends to slow down the liver’s process of making sugar from protein. The bad news is that most overweight people are insulin resistant, so their insulin is unable to act to its best advantage.
Additionally, remember that dietary protein is not the only source of amino acids. I explained previously that the blood contains amino acids at all times, and that fasting does not reduce the amount of them. Recall also that all tissues are breaking down and building up constantly. This means that even if you were to eat no protein at all, amino acids would nevertheless be present because of the breaking down of your tissues, and the liver would be able to convert those amino acids into sugar.
What To Do
Now that we are all completely afraid to eat ANYTHING, we still have to try to put together a dietary plan. We want to keep our carbohydrates low, but we don’t want to get all our carbs from the conversion of protein, because we want to get the important vitamins, minerals, and fiber from vegetables. So, we follow a low carb system of eating between 20 and 60 grams of carbohydrates, and we eat protein and fat.
But, often we don’t lose weight, or at least not fast enough to suit us. We can now see that the amount of protein we eat plays an important part in this. We must eat protein, or suffer the consequences of lost muscle mass or worse, but how much protein do we need?
There have been many studies. None of them are terribly conclusive, but we have to start somewhere. A good estimate for adults (not pregnant or breastfeeding women, not children, and not teenagers) is that the protein requirement ought to be about 2 grams of actual protein per 5 pounds of ‘ideal’ body weight.
For example, if you think you ought to weigh 150 pounds, divide the 150 pounds by 5, and multiply that number by 2 grams. The answer to this example is 150 divided by 5 is 30, times 2 is 60. If your goal weight is 150 pounds, you need about 60 grams of protein each day. Remember that this means protein grams, not the weight of the food containing the protein.
However, since you probably don’t yet weigh your ideal weight, more protein may be required to maintain your body’s protein structures the way they are now. To be safe, we can figure a higher protein allowance, say 10 to 20 extra grams of protein per day, depending on how much you currently weigh in excess of your ideal weight.
How Much Protein Will Be Converted To Carbohydrates From Our Protein Intake?
Now, for fun or horror, (depending on how you look at it), we can calculate how many hidden carbohydrates the person in our above example will get from eating her required amount of protein. Since an average of 58% of the protein can become carbohydrate, we multiply 60 protein grams by 58%. The answer is about 35. Depending on how a person’s body uses the protein it needs, as many as 35 extra carbohydrate grams may be available from 60 grams of protein consumed, in addition to the amount of carbohydrates that the person is getting from eating other carbohydrate foods.
There are two questions that you are likely asking yourself right now. The first question is, “Why hasn’t Dr. Atkins talked about all this?” I think the answer is that since everyone must eat their required protein, and since many people can lose weight without concern for how much excess protein they are eating, low carbohydrate plan experts merely avoid talking about it. But, be assured that when Dr. Atkins, the Drs. Eades, Dr. Schwarzbein, or any of the others tell you to start your carbohydrate counting at 20, 30, or 60 carbs per day, they already are taking into account that you will be getting carbohydrates from protein conversion. This is one of the reasons why the amount of allowed ‘regular’ carbohydrates is so small.
The second question you are probably asking yourself is, “Are you going to tell us next that fat grams convert to carbohydrates, too?” Well, boys and girls, we will go into the whole story of dietary fats starting in a few weeks, but for now, the quick answer is: Yes, but not much; only about 10% of fat grams convert to sugar.
In the past ten articles, I have brought you down both the Carbohydrate Trail and the Protein Trail. We are now ready to consider what new thoughts and new ideas we can make from all the information. Next time we will discuss what conclusions we can reach from the facts we have learned about carbohydrates and protein I hope you will join me.
The Science of Low-Carb & Keto Diets
|About Dr. Beth Gruber
Dr. Gruber is a graduate of the Southern California University of Health Sciences and has been in private chiropractic practice in Long Beach, California since 1964. She also received both a Bachelor’s Degree and a Master’s Degree from California State University at Long Beach. She has written on health-related subjects for over 30 years, for several different publications. She lives in Southern California with her husband of 33 years. Both she and her husband follow and live the low-carb lifestyle full time.
Article 11 of the Science of Low-Carb & Keto Diets series. Since some of the protein I eat converts to carbs, can I eat only protein if I take supplements to provide what I'm not getting in veggies?