How Much Processed Food is Healthy?
I got an email from a reader who runs a vegetarian organization saying that he has been receiving a lot of questions about processed foods. He passed on the questions to me and asked me to write an article. Here are the questions:
1. The main questions/statements I’ve been getting are largely of the “all processed foods are poison” and “are vegan processed foods similar to processed meats?” I doubt that vegan meats contain nitrites, for example, but i do wonder if you know of any connections between vegan meats and bowel cancer.
Nitrites are used to cure meats in order to reduce bacteria growth, but are not used to cure vegan meats. Another concern with meats are the heterocyclic amines formed especially in burned meat. These are not found in vegan meats.
2. “What about all of the salt in tofurky?” and the like?
The amount of sodium in processed foods is something that you should pay attention to.
Recently, there has been a big controversy over how much sodium people should aim for. You can read a concise summary of the controversy in The New Salt Controversy from the Harvard School of Public Health. A summary of the article is that there is good evidence that all Americans should aim for a daily sodium intake of no more than 2,300 mg. Additionally, people with elevated blood pressure should aim for a sodium intake of 1,500 mg, and this might even be a good idea for almost everyone.
If you have blood pressure on the lower end of normal, then it’s not so necessary to aim for 1,500 mg and, in fact, the Mayo Clinic recommends that people with hyoptension actually eat more sodium (see Low blood pressure: Treatments and Drugs).
One thing to be aware of when reading about sodium is the difference between salt and sodium. Salt is sodium chloride and 10,000 mg of salt equals 4,000 mg of sodium.
High sodium intakes can also contribute to calcium loss from the bones, kidney stones, and possibly stomach cancer. You can read more details in the Linus Pauling Institute’s article Sodium. My sense from the article is that sodium intakes as low as 2,300 mg per day probably do not contribute to these diseases. The article also points out that a diet high in fruits, vegetables, and legumes may help counteract the effects of a high sodium intake on blood pressure.
So what does this mean for vegans? One, you should regularly get your blood pressure tested. Two, unless it is so low that you don’t feel a need to limit sodium intake (and I cannot answer this question for any given individual, you would need to talk to your physician), aiming for as low as 2,300 mg/day is important. If you are at risk for, or have, high blood pressure, limit sodium intake to 1,500 mg per day.
Sodium is mostly found in processed foods. If you do not add salt to whole plant foods, they will contribute almost no sodium. Carrot juice is one exception and there might be some others. In fact, a completely whole foods vegan diet might not meet the DRI for sodium of 1,500 mg for people 9 to 50 years old (see Sodium for the DRI for other age groups).
For a vegan to figure sodium intake, they only need to worry about the processed foods or added table salt (a teaspoon of table salt contains 2,325 mg of sodium).
Here might be a typical day of high-sodium foods for me:
1 cup soy milk – 95 mg
1 serving Tofurky – 320 mg
2 slices bread – 360 mg
1 Trader Joe’s chocolate chip cookie – 65 mg
1/2 serving sesame sticks – 175 mg
2 cups popcorn – 100 mg
1/2 cup carrot juice – 90 mg
1 1/2 T salad dressing – 213 mg
Dessert – 100 mg
Other – 500 mg
Total 2,018 mg
On this regimen, I have kept my blood pressure on the lower side of normal, though I should also point out that during the warmer months I exercise in the heat and sweat out a lot of sodium.
As you can see, I don’t particularly shy away from processed foods. Of course, I do eat fruits, vegetables, grains, nuts, and beans in addition to these foods.
3. “Why are so many people opposed to artificial meats?”
Let me count the ways.
Probably the most common objection is because many of them contain isolated soy protein. As the Declaration of Independence says, “We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, and that isolated soy protein is hazardous to your health.”
Joking aside, many people think that isolated soy protein is harmful. I have not seen the evidence for this, but I can understand why someone might want to approach it as “guilty until proven innocent.” If you are such a person, Tofurky does not use isolated soy protein in their meats. And Field Roast does not use any soy at all – they use gluten, which doesn’t sit much better with the whole-foods-only crowd!
Another objection is that people consider processed foods to be devoid of nutrients. You shouldn’t rely on only processed foods for all your nutrition, but even isolated soy protein isn’t completely devoid of nutrients (click here for nutrient breakdown).
Finally, some people think that it’s hypocritical for vegetarians to want to eat something that has the taste and texture of meat. These people are clueless as to why most people become vegetarian.
4. “What processed foods should I limit my consumption of?”
You can overdo any processed food, or any unprocessed food, for that matter. It really depends on your overall diet and how many total calories you’re eating.
If I have to pick foods to limit, I would suggest limiting fried foods to a couple servings per day and then watching your sodium intake as described above. Ten servings of soy per day is probably pushing the limits of wise dietary practices. Don’t cook with oils that are high in omega-6 fats; if you cook with oil then olive is probably the best. Too much refined sugar isn’t a good idea, though I don’t know what “too much” would be for any given individual. Dried fruit can cause cavities so I’d limit to a couple servings a day.