Peanut butter and Bamba snacks

This is a picture of my daughter when she was seven months old. I buckled her into her highchair with a pile of puffs in front of her and served my 3 year old a peanut butter sandwich.  Then I turned my back.  It was just enough time for my baby to grab the table cloth, pull her brother’s plate across the table, and get her hands and mouth on a piece of sticky, gooey, peanut butter sandwich. She was quite pleased with herself as you can see. I posted the picture to my facebook page with the comment, “What would the AAP say?” I was actually referring to the act of leaving her unattended long enough to get her hands on a food that was a little too advanced for her and posed a choking risk. However, the comments that my friends left centered on the risks and benefits of early peanut exposure and allergies.

The literature and the AAP recommendations have gone back and forth on early exposure of infants to allergenic foods. When I was in medical school, we recommended avoidance of foods like peanuts, tree nuts and eggs. When I was in residency, the AAP formally rescinded this recommendation citing too little evidence to support it. At this point, small observational studies started to appear showing decreased rates of severe allergy with early exposure to allergenic foods but none of them were strong enough to provide a clear answer. As a result, different pediatricians were giving different advice.

Last week the New England Journal of Medicine published one of the largest studies looking at the effects of early exposure to peanuts on the development of peanut allergy. 600 babies between the ages of 4 and 11 months were enrolled in the study.  All of the kids who participated in the study had either severe eczema (a skin condition associated with food allergy) or confirmed egg allergy or both, indicating a predilection for food allergies in these individuals. A small group of participants had mild hypersensitivity to peanuts at the beginning of the study. The babies were randomly assigned either to avoid peanuts entirely until they were five years old or to receive peanut products in their diets regularly until they were five years old. After five years, every child in the study was fed peanut butter and monitored for signs of allergic reaction. The results? The kids who were exposed to peanuts for the first five years of life had significantly lower rates of peanut allergy than the kids who avoided peanuts completely. This was also true for the kids who showed mild hypersensitivity to peanuts at the beginning of the study.

Like any good study, this paper has people asking a lot of questions. What does this mean for babies who are at high risk for peanut allergy? What does it mean for kids without eczema or food allergies? How in the world to you expose babies to peanut products that are not choking hazards?

This article has had a huge impact on the discussion of when to introduce peanuts but it is by no means the last word on the subject. The study only included kids at high risk for peanut allergy so it is difficult to say with certainty if kids at low risk would respond in a similar pattern. Kids with mild reaction to peanuts at the beginning of the study were included, but those with a severe reaction to peanuts did not participate. Moreover, the study only looked at peanut exposure and peanut allergy. It did not evaluate other highly allergenic foods like seafood, tree nuts and wheat. And while the study has good data, early introduction did not work for everyone. Nine of the kids assigned to the peanut eating group withdrew from the study because they began to develop allergy symptoms.

For kids with a history of food allergies, eczema or a concerning family history, decisions about allergenic food introduction need to be made in conjunction with a physician who knows them well.  In my family, we do not have a significant history of food allergies. I introduced peanut products to my two older children before they were a year old. After reading this study, I will still plan to introduce peanut products to my youngest before she turns one, perhaps with a little more confidence.

And how do you introduce peanuts to babies? The study used Bamba snacks, which are apparently quite popular in Israel. They are corn puffs that are coated in peanut butter and dried. Out of curiosity, I ordered some. They are crunchy and taste like peanut butter. For the purposes of the study, the snacks were softened into a paste for babies who could not tolerate the crunchy texture. I thought my youngest might get to try Bamba snacks in a month or two but with the way my big kids are scarfing them down, they may not give her a chance.

*Disclaimer: The people who make Bamba snacks do not know who I am. I am not endorsing their product and I am not getting paid to tell you that my kids think their snacks taste good.

Thoughts on the HPV vaccine

A friend of mine recently asked me about the safety of the Human Papilloma Virus (HPV) vaccine. She had heard some scary stories about the vaccine and did not want to subject her children to something that could be dangerous. As a mom, I completely understand the desire to protect your children and make the best decisions for their health and safety. This is why we use car seats, put our babies to sleep on their backs and fuss about eating enough vegetables. This is also why I vaccinate.

There is a lot of misinformation about vaccines in general and Gardasil especially. Just last week the Toronto Star – the biggest newspaper in Canada – published an “investigation” about side effects rumored to be associated with Gardasil. For this article, the author failed to interview anyone in the medical community or cite any of the studies formally evaluating the safety of the vaccine. The article has since been retracted and while it was embarrassing for the newspaper, I think it is also a reflection of how pervasive vaccine rumors are in our society.

The HPV vaccine (available in the US as Gardasil or Cervarix) has a lot of the same side effects as other vaccines – pain, local reaction, allergic reaction in some people, etc. Its unique side effect is syncope, or fainting. I think every pediatrician I know has seen at least one kid get the Gardasil shot and get a little light headed afterwards. This is in part because it is a painful shot. The other part of it is that teenagers faint more frequently than little kids and adults (for all kinds of reasons).

The other stories about bad things happening after receiving the vaccine are just stories with no data to support causality. There is a database called the Vaccine Adverse Event Reporting System where anything bad that could possibly be related to a vaccine is reported. Anyone can contribute. If you search the database, you will see there are three children under the age of 12 who were in car accidents some time after receiving vaccines. The vaccines probably did not cause the accidents. There are 40 reported cases of acne after receiving Gardasil. Did Gardasil cause the acne or did acne develop because the teenaged patients were already predisposed to developing acne, with or without the vaccine? The purpose of VAERS is to continue to monitor the vaccines for safety. It is good to have this system in place. It is not reasonable to do a scientific study for every story but if enough accumulate (there are over 3,000 reports of syncope after Gardasil injection) then it is reasonable to structure a formal evaluation to determine if there is a true association or just coincidence. One side effect of this effort is that it seems to give some credibility to stories that probably are not related to the vaccine.

Everything we do has risk. Gardasil does have an increased risk of fainting immediately after injection. There is no scientific evidence substantiating other scary rumors. There is good, solid evidence that it protects against the two strains of HPV that cause 70% of cervical cancer. And HPV infection is incredibly common. 50% of sexually active adults carry HPV. In 2008 there were 20 million new HPV infections in the United States. Cervical cancer is the only cancer we test for in healthy people under the age of 40. I never want my daughters or anyone I care about to have to worry about a positive pap smear. I absolutely will vaccinate my kids against HPV.

The only thing to fear is fear itself: A breakdown of vaccine ingredients

Let’s talk about vaccine ingredients. I am reading less about vaccines causing autism (we all know that theory is utter nonsense, right?) and more about vague concerns regarding the chemicals in vaccines. To begin with, we are surrounded by chemicals. Water (H2O), caffeine (C8H10N4O2), sugar (C12H22O11) are all chemicals.  But perhaps it is the unfamiliar ingredients that people find intimidating. 

Let’s tackle the ingredients in the Measles,Mumps, Rubella and Varicella (MMRV) vaccine and see what there is to fear:

sucrose, hydrolyzed gelatin, sorbitol, monosodium L-glutamate, sodium phosphate, albumin, sodium bicarbonate, potassium phosphate monobasic, potassium chloride, potassium phosphate dibasic, neomycin, bovine calf serum, chick embryo cell culture, WI-38 human diploid lung fibroblasts, MRC-5 cells.

That is 15 ingredients in one 0.5mL injection. Grab a cup of C8H10N4O2 because we are going to cover each one. The last four, bovine calf serum, chick embryo cell culture, WI-38 human diploid lung fibroblasts, and MRC-5 cells, are the ingredients used to make the attenuated live viruses used in the vaccine.  They also sound the most foreign, so I will start there.

A virus is a parasitic microorganism. It has to invade a cell and use the cell’s resources to survive and replicate. In order to make viruses for use in vaccines, scientists must first grow cells to host the virus. Bovine calf serum is used to provide nutrients to the cells. The types of cells used are named in the list of ingredients. Chick embryo cells are able to grow measles and mumps. A human cell line of fibroblasts (a fibroblast is a type of cell) called WI-38 grows rubella virus. A second human cell line called MRC-5 grows varicella.

Making these viruses attenuated, or weak, and suitable for vaccines involves gradually decreasing the temperature the cells are grown in over generations of viral replication. Normal measles virus prefers to replicate at human body temperature. With the decrease in temperature, the laboratory virus population adapts. Subsequent generations become proficient at replicating at 83 to 93 degrees Farenheit (instead of 98.6 degrees). When this weakened virus is injected into your body and subjected to normal body temperature, it is sluggish and slow and your immune system is able to kill it off before it is able to establish infection.

When the generations of attenuated virus have developed, the infected cells are put in a centrifuge. This machine rapidly spins the cells, rupturing the walls and allowing the virus to separate away from the other cell contents. The virus is then available to be placed in the vaccine. The cells and the serum that helped grow them are listed as ingredients, but in reality there is only a possibility of trace remnants present in the actual vaccine.

Neomycin is an antibiotic to keep bacteria from contaminating the vaccine. Neomycin is the same antibiotic present in Neosporin and triple antibiotic ointment. There are 5 micrograms in the vaccine injection. This is approximately 1/500th of the amount of neomycin present in the amount of neosporin that you would apply to a small cut.

The rest of the ingredients are used to maintain the pH and the stability of the virus so that it is still alive and potent enough to allow you to develop immunity when you get your shot.

Sucrose is table sugar. 20 milligrams of sugar, or 1/200^th of a teaspoon, are present in the vaccine.

Sodium bicarbonate is baking soda.

Hydrolyzed gelatin can also be found in Jello.

Sorbitol is also used as an artificial sweetener in chewing gum and Vitamin C tablets.  Your body makes sorbitol during the sugar break-down process.

Monosodium glutamate aka MSG, is an amino acid known for giving umami flavor to many Chinese dishes. It is also found in mushrooms and breast milk. There is more MSG in a fresh tomato than there is in the MMRV vaccine.

Albumin is a protein. In fact, it is the most abundant protein in your blood plasma. Every day your liver makes about 40,000 times more albumin than the amount present in the MMRV vaccine.

The rest of the ingredients: sodium, potassium, phosphate and chloride are electrolytes that your body uses every day. 

To sum up, we have three kinds of cells that are not actually present in the vaccine. Cell food, which is also not in the vaccine. An antibiotic to keep the vaccine free of bacteria. 2 ingredients that your body makes naturally. 4 ingredients that are in my kitchen cupboard right now, except in vastly greater quantities. And electrolytes that our bodies take in and use and excrete on a daily basis. I do not think these chemicals sound scary. In fact, I think the chemicals that we use to prevent people from dying of dehydration, respiratory distress and bacterial super infections (all of which can happen as a result of measles infection) are more complex and bring with them more potential for side effects than any of the chemicals found in the MMRV vaccine.

If you still find the chemicals that make up the MMRV vaccine intimidating, please leave a question in the comments below.