Tuesday, June 21, 2011

An apple a day.

We all know that to be healthy, we should eat our vegetables. But how many veggies do we really need to get the essential vitamins and minerals we need for our bodies to function properly? Am I getting everything I need from my food? These questions struck me as I was putting together my weekly meal plan, so I decided to do a little experiment.

Over the past five years, I’ve been slowly transitioning from a typical pizza-and-soda lifestyle to a veggie-centric, low-meat diet. More recently, after years of digestive issues*, I have completely stopped consuming any dairy products and reduced my intake of grains. Giving up these (often fortified) foods means I rely heavily on fruits, vegetables, nuts, and legumes for nutrients. In a day of prolific vegetable-eating, can I get the recommended daily allowance (RDA) of all my nutrients?

For my experiment, I decided to eat a large salad for lunch and pasta with shrimp, tomato sauce, and extra veggies for dinner. (Pasta is a rarity for me, and frankly, my stomach did not appreciate it!) I aimed for lots of greens and lots of variety, especially in the salad. I also ditched the traditional salad bowl and made a huge plate instead. These are the ingredients I used:

Super salad (5-6 servings):
  • ~8 cups of green leaf lettuce
  • 3 carrots
  • 3 zucchini
  • 1/2 red onion
  • 5 cups broccoli florets
  • Topped with 1/2 cup steamed lentils (pre-cooked from Trader Joe’s), ~10 blackberries from my porch, 1 avocado, and ~1 tsp balsamic vinegar per serving

Shrimp pasta with extra veggies (6 servings):
  • 8 cups chard, chopped
  • 4 cups kale, chopped
  • 3 zucchini
  • 4 carrots
  • 1 jar TJs Organic Tomato Basil Marinara sauce
  • 1 pkg TJs Vegetable Radiatore pasta
  • 1 lb large cooked shrimp (frozen from TJs)

I cleaned and chopped everything at once, and stored the salad in a huge airtight container in the fridge to eat throughout the week. It took less than an hour to clean, chop, mix, and store everything. And I was all set to make a quick and easy dinner.

Getting the stats.

Because I eat mostly whole foods, it was pretty easy to find out the nutritional content of my meals. Nutrition labels on packaged foods don’t usually report the quantities of micronutrients, such as vitamin B-12 or vitamin D, although some fortified foods, like cereal, tend to supply more information. I found three websites that were helpful in determining the nutritional value of my foods:

(1) Fit Day – Similar to Daily Plate (via Livestrong), Fit Day is a tracking system that allows you to add foods to a food log and automatically computes the nutritional load. Whole, unprocessed foods like apples or chard have all the micronutrients listed. Fit Day also offers weight tracking, mood journals, and other health and wellness tools. The charts I will show later all come from Fit Day’s food log tool.

(2) The USDA National Nutrient Database – This site allows users to search for foods and supplies nutrient information. The site looks dated and uninspiring, but it’s easy to use. I checked some of the values from Fit Day against these numbers, and they are the same. If you have a specific food you want to check out, this is a good place to go.

(3) Nutrition Data (by Self Magazine) – Somewhat surprisingly, this site was one of the best I have seen for accessing and interpreting information on individual foods. In addition to the standard nutrition label and tables of micronutrients, the site also displays several graphics to help users understand how the numbers relate to overall healthfulness. The site also appears to have tracking capabilities though I have not tried them out. There is certainly much more to explore here!

And now, the moment of truth.

Given my massive quantities of veggies, certainly I consumed everything my body could possibly need, right? Well, almost. Below, I have pasted in two charts from Fit Day showing the nutrients I consumed in my salad, pasta dinner, and the apple and 1.5 Tbsp of almond butter I had for breakfast. I had a few lentil chips too, but since they are processed, I have no way of getting their nutrient load and thus didn’t bother adding them in. I had the same problem with the pasta and pasta sauce (although I did include the nutrient info from the labels), so I may have gotten slightly more nutrients than the graphs show. Unless they are fortified, processed foods tend to have lower nutrient loads than whole foods, so this is likely a small effect.

As you can see in the table and chart, I did fairly well. I achieved at least 90% of the RDAs of most nutrients, and had way more than I needed of vitamins A, C, and B6 and the minerals copper and manganese. I also got plenty of fiber. However, several of my other B-vitamins, (such as niacin and thiamin) were rather low. I was also low in Calcium (44%), vitamin D (42%), and somewhat low in iron (78%). At only 16% of the RDA, my B12 level was most alarming. Most people get calcium and vitamin D from dairy, B-vitamins from fortified cereal, and iron from red meat. In my low-meat, low-wheat, no-dairy diet, perhaps these deficiencies are to be expected.

Isn’t it iron-ic?

According to the CDC, plant sources of iron are harder for the body to absorb than animal sources. That means my low iron level may be even more problematic given that most of my iron is coming from plant sources. I got nearly 20% from a half cup of lentils versus only 7% from the shrimp, my only animal-based food that day. Consuming iron with calcium can reduce absorption whereas vitamin C aids absorption.

Interestingly, even though our population typically consumes quite a lot of meat, the CDC names iron as the most common deficiency in the U.S. population. Eating meat isn’t necessarily a silver bullet, so we all need to be cognizant of our iron intake. People on diets low in animal products may need more iron than they realize due to the absorption issues.

The Bs have it.

Vitamin B12 is even more troublesome for people who do not eat animal products. According to the National Institutes of Health, B12 is important for proper nervous system, blood, and cellular functions. It is only found in animal-based foods, fortified foods, or as a supplement. Lack of B12 in adults can cause anemia, fatigue, numbness, and a host of other problems (see the fact sheet for a comprehensive list). Lack of B12 during pregnancy can be especially harmful to the developing fetus.

Apparently, a lot of B12 gets stored in the liver. Several vegetarian and vegan websites suggested that stored B12 can get a person through many years without consuming animal products or supplementary B12. I was able to confirm this via the Mayo Clinic. However, I was unable to find recommendations of how often a person should eat animal products to maintain B12 levels over the long term. People who have never eaten much meat may want to consider a supplement. And again, pregnant women need to be especially careful because a fetus has no liver stores to draw upon.

Folic acid (or folate) is an essential B-vitamin used in many cellular processes. We all need enough folic acid in order for our bodies to function properly, but here too, pregnant women need to be extra careful. According to the CDC, folic acid deficiencies lead to really awful birth defects such as spina bifida (malformation of the spine), cleft palate, and brain defects. Not something you want to mess around with!

FitDay doesn’t track folic acid, so I had to rely on the other sites to determine my intake. The half cup of lentils I had on my salad gave me 45% (!!) of my RDA. One medium zucchini gave me another 14%, one cup of broccoli florets offered 13%, and the other veggies each had 1-5%. In total, I had about 90% of my folic acid RDA from these foods.

Boning up on veggies.

I was low in bone-building nutrients, vitamin D and calcium. Vitamin D is notoriously difficult to get from food, but quite easy to get from sun exposure. Of course, lots of time in the sun has its own risks. Getting the RDA of calcium is also hard without consuming dairy or fortified foods. The Paleo Diet community has spent a great deal of time on this point because dairy is not considered Paleo (read more here and here). They argue that we don’t need as much calcium as the RDA suggests as long as we are consuming the proper foods. On a Paleo Diet, they claim, your body absorbs much more calcium than on a standard Western diet, so you don’t need to consume as much. While a sensible argument, I’m not sure I’m willing to bet my health on it.

Supplemental information.

This experiment has taught me that, as long as I plan to eat a low-meat, low-wheat, no-dairy diet, I would gain some peace of mind by adding supplements. I will be adding a calcium/vitamin D supplement as well as an iron supplement (to be taken separately to aid absorption!). Before I invest in a B12 supplement, I want to check with my doctor. I want to understand how often I need to eat animal products in order to keep my B12 at a healthy level even on days when I don’t have any animal products. In the meantime, I’ll order more ethical eggs from the Eatwell Farms CSA to make sure I’m getting more B12, more often. Lastly, I am going to supplement my folic acid intake. Some people are poor absorbers when it comes to folic acid, and I happen to be one of them! Even though I get nearly the entire folic acid RDA from food, it may not be enough for my body.

I have also learned that I probably eat too few calories. Breakfast, lunch, and dinner accounted for only 1100 calories. Adding in nuts and fruit as snacks, and some more legumes, would help me get more calories and more nutrients. Beans and lentils are especially high in iron – as much iron as meat in many cases – and also contain calcium.

Finally, this experiment really made me wonder how I survived on my old diet, and how the rest of the population does so. I used to hear “eat more vegetables” and respond by adding more tomato sauce to my pasta or eating a few extra potatoes. It didn’t occur to me that I was supposed to be eating several cups of leafy greens a day or that vegetables should play the starring role in all my meals. I wonder if the migraines, heartburn, and dizzy spells that I considered normal just a few years ago were my body’s way of telling me that it was sorely deprived. It’s amazing to me that we can eat so many calories and yet consume so few nutrients.

Even with all the changes I have made over the years, this experiment included more vegetables than I usually eat. It wasn’t hard, and actually, I really enjoyed having a giant salad for lunch. I think this experiment has helped me turn a corner. Understanding my nutritional needs based on my particular eating habits makes me feel more secure and allows me to be a healthy and well-functioning human. I hope that reading this inspires you to do a similar experiment. If you are eating a lot of processed foods, then getting micronutrient information may be tricky, but it’s worth the effort.

A healthy diet isn’t about weight loss or fads – it’s about living up to your potential and feeling confident in the choices you make. If you find that you are low in a lot of these nutrients, check with your doctor to make sure the information I have gathered is right for you. And remember to eat more vegetables – a LOT more vegetables!

For tips on getting more fruits & veggies and healthy eating even on a budget, check out:
Fruits and Veggies Matter (CDC)
Choose My Plate (USDA)

* If you have any GI issues at all, I strongly recommend a full-stop on dairy and/or grains for two weeks. If you are intolerant, as I am, eliminating these foods will make you feel better than you can even imagine right now! Complete elimination is tricky. It takes a lot of label-reading and care. It really is worth it, though, to feel truly healthy and normal.

1 comment:

  1. I love the way you label the photos, it makes it so much more enjoyable to read about the recipe! And I love chard! Nice post! : )