A viral Internet story has ben making the rounds about of Loni Jane Anderson, a 25-year-old pregnant Australian woman on a vegan diet that involves 10 bananas a day and is 80 percent carbs, 10 percent fat and 10 percent protein. Could this possibly be healthy? And could someone overdose on potassium by eating all of those bananas?
To take the easy question first, you can’t OD on potassium by eating bananas. The lethal dose of potassium is 2500 mg of potassium per 2.2 pounds of body weight, consumed all at once, and a banana has about 420 mg. So even if you weigh only 100 pounds you’d have to eat 270 bananas in under a minute (and the potassium would be the least of your problems). The USDA, the U.S. federal agency that sets the recommended daily allowances of macronutrients, vitamins and minerals, suggests that pregnant women get 4,700 mg of potassium a day (5,100 if you’re breastfeeding). Fortunately potassium is available in plenty of other foods and is probably in your prenatal vitamin as well, so you don’t need to eat 10 1/2 bananas.
On to the more complicated question: can a vegan diet of 80 percent carbs, 10 percent protein and 10 percent fat be healthy? Protein is a vital building block of cells, both yours and your baby’s, and too little can lead to fatigue, listlessness and extreme fluid retention. It’s especially important to get enough protein in the second and third trimesters, when the baby puts on a lot of weight. The USDA suggests a dietary breakdown for pregnant women that works out to about 66 percent of calories from carbs, 25 percent protein and about 8 percent fat, or about .5 grams of protein per pound of body weight a day. If you’re 135 pounds that works out to about 67.5 grams of protein a day.
With a vegan or fruit diet, the big issue is being able to eat enough food to get all of that protein. While nuts, beans and tofu do have protein, it would take almost four cups of almonds to get 67.5 grams of protein, or 1 3/4 cups of black beans, or about 3 cups of tofu, compared to about 5 ounces of turkey breast for the same amount of protein. So if you are a vegan, getting enough protein is certainly possible, but because of the amount of food you need to eat it’s not always easy, especially in late pregnancy when your stomach is compressed and you can only eat a little bit of food at a time. While pregnant women in general should aim for eating 6-8 smaller meals a day (instead of three big ones), if you’re a vegan you may find you need to eat every half-hour in late pregnancy to get enough nutrients.
And is 80 percent too high of a percentage of carbs? Not necessarily, because it matters what form the nutrient is in. While technically 100 grams of carbohydrates is always 100 grams of carbohydrates if you’re eating it in the form of two mangoes or half a cup of table sugar, the time it takes for you to actually eat the fruit and then digest the fiber in the fruit will slow down absorption, giving you a chance to use those carbs for energy before they get stored as fat.
So could this diet be healthy? If you’re averaging .5 grams of protein per pound of body weight a day with carbs are from fruits, vegetables and whole grains, if you’re gaining weight, feel energized and aren’t experiencing symptoms of protein deficiency, it is possible. But if you’re on a vegan diet and feel tired, listless, have muscle fatigue or are severely retaining fluid, let your health care provider know right away and take action to up your protein somehow, either by adding a vegan protein supplement to your food or compromising and adding some eggs or dairy.
And if Loni Jane Anderson snuck dairy or eggs we don’t know, but she did give birth to a health 8 pound, 7-ounce baby boy.