The high-protein diet debate

A few months ago, new research was published that indicated people who eat high-protein diets during middle age are more likely to die of cancer than those who eat less protein. Clearly this was an alarming announcement to some and concerning to others.

The research followed 6,000 people, 50 years old or older for 18 years. What they concluded was that the people who eat a high, animal-based-protein diet were four times more likely to die of cancer then those who eat a low-protein diet.

Now, there is much that we do not know about the variables regarding other health and fitness habits of these study participants. Did they smoke, drink alcoholic beverages, eat whole foods or processed foods, and what were their daily fitness levels?

There are many correlations which need to be examined, and with each person's overall health habits differing so much, shouldn't that be factored into the equation? A simple correlation of high animal-based-protein diet and cancer does not statistically prove causation in every person who eats that way.

The other interesting point in the study: plant-based protein apparently does not interact the same way in the body and does not feed cancer cells.

So is plant protein good and animal protein bad? I think we all have seen that memo before, and yes I agree, vegan and vegetarian diets are healthier - but let's face it, animal-based foods aren't going anywhere.

Most people like dairy or meat products on occasion, and all things in moderation is still the best approach. The idea that we should switch to a plant-based protein diet would be a challenge for a majority of people, so that is not very practical.

I personally believe if you eat whole foods, reduce sugar intake (which was not closely examined in the study) and stay active and fit, that lifestyle offsets any concerns with high levels of protein, which is vital to your health.

I also believe it best to consume protein from both animal- and plant-based sources. For some, plant-based protein is the only way to go and that's great, but as stated it just does not work for everyone.

With that said, let's take a look at why you need to keep protein at adequate levels when you age.

Many people are living longer and more active lives. Good nutrition is a very important aspect to keep yourself in good health. With so many quick-and-easy processed foods out there, mostly loaded with empty carbohydrates and tons of sugar, it is a challenge to have a balanced diet with enough protein.

Specifically, men and women older than 40 should ensure they are getting enough protein in their diet. Women need to pay close attention to their protein intake since they require more of it to keep healthy compared to men of a similar age.

As we age our body composition changes and we start to have a reduction in total body protein. We know that as we age we lose muscle and bone density. These losses can lead to a number of health issues like osteoporosis, reduced immune function, a loss of skin elasticity and muscle tone.

Protein is a critical component in your diet and helps you repair muscle, grow tissue, regulate hormones, control metabolism and maintain a healthy immune system, among other benefits.

Many people do not understand or underestimate the importance of protein in their body. Your body is made up of muscles, connective tissue, organs and bones that are made of protein. Protein makes up about half of your non-water body mass.

So how much protein does the average person need each day to stay healthy? According to the USDA, the recommended dietary allowance for adults for protein is 17-21 percent of your daily caloric intake. Now how does that break down in grams per day? According to USDA guidelines, the average adult requires 0.36 grams of quality protein per pound of body weight daily.

Some studies suggest that older people who have an active fitness and exercise lifestyle need to increase their protein intake significantly. It is also recommended that people who are healthy, but sedentary, should stick with recommended USDA averages.

Confused yet? Here is a great way to establish where you may fall on the protein intake scale.

Take your weight in pounds and divide it by 2.2, which is your weight in kilograms.

Multiply the weight in kilograms by either 0.36 if you're mostly sedentary, by 0.80 if you're moderately active, or as high as 1.8 if you're very athletic. This figure is your recommended daily requirement of protein in grams.

Using my weight as an example:

178 pounds / 2.2 = 81 (rounded up)

81 X 1.8 = 145.8 grams of protein per day

The body's proteins are continually in use and the more active you are, the quicker your protein is broken down, and your need for more protein increases. Protein, unlike fat or carbohydrates, cannot be stored for later use, so a daily fresh supply is required.

Now let's take a look at what makes up protein. Protein is made of amino acids, which consist of four elements: nitrogen, carbon, hydrogen, and oxygen. There are 23 amino acids, which include Lysine, Threonine, Tryptophan, Leucine, Valine and Isoleucine.

Your body can manufacture 14 of the 23 amino acids it needs. There are nine amino acids your body cannot produce; they must be provided by your diet. As we get older it is more important to understand your nutritional needs. Getting enough protein is part of that, but without over-consuming protein.

It is important to understand you cannot live on lean protein alone and over-consuming can be harmful to your kidney function. When the amino acids are not used, they are converted to calories. This process of converting protein or amino acids to calories removes the amino acids of their nitrogen, creating nitrogen waste. This nitrogen waste arrives to your kidneys as toxic urea and must be filtered out.

The National Kidney Foundation estimates that about 20 million Americans have some form of reduced kidney function and don't even know it. Processing the urea or toxic nitrogen waste can stress the kidneys. If this happens in large amounts, it can cause further damage to weak kidneys.

You need to ensure you are getting a balanced diet with enough protein to keep your body healthy and happy. Approach protein with moderation. If you have questions or concerns about your daily intake of protein or if you feel a pre-existing medical condition could be challenged by too much protein intake, check with your physician.

Judd Jones is a director for the Hagadone Corporation.