Category Archives: All

Do microwaves cause cancer?

image from

Microwave ovens are appliances that dominate almost every kitchen in the United States. Since their increasing household use in the 1980s there were rumors of risk from microwaves. The Think Twice Blog exists because the momentum of such “myths” can carry them for decades after they are proved false. To this day, as we reheat our leftovers in a microwave, we may stop to think twice about whether the convenience of a quickly heated meal is worth the potential risk of exposure to microwave radiation. Afterall, the sun can cause cancer due to ultraviolet (UV) radiation, and we have probably all heard not to stand too close to microwaves at some point in our lives. But do you actually have to worry about developing cancer from microwave radiation? 

Radiation is used to heat up our food. However, the radiation emitted by microwaves is low-energy. On the other hand, UV radiation is high-energy and can damage DNA in our cells. DNA damage can lead to cancer, which is why we protect ourselves using protective sunscreen. In contrast, microwave ovens only have enough energy to vibrate the water molecules in our food. This movement of water molecules creates the water vapor that heats and cooks our food, similar to how we generate heat when our hands rub together. The Minnesota Department of Health states irradiated energy passes through the food like”light through a window” which is also why food heated in a microwave is not radioactive after it is heated.

The potential harms of microwave radiation are minimal. Microwaves are very closely regulated to prevent high levels of radiation leakage through provisions such as safety locks to prevent the oven from operating when the door is open. The FDA allows 5 milliwatts per square centimeter of microwave radiation leakage two inches away from the microwave or farther, which is far below the level known to be harmful to humans. While we can decrease our exposure to microwaves by standing further from the device while it’s on, the waves emitted from this device are not dangerous to humans at any distance. 

Keep in mind that if your microwave is damaged in any way, it is best to not use it. However, in most cases, we can enjoy the convenience of microwaves without fear. No, the convenience of microwaves is not too good to be true. Enjoy those wonderful reheated seconds!

10,000 Steps: Just a Number?

We have all heard 10,000 as the magic number of recommended daily steps. In fact, your FitBit vibrates and fills the screen with streamers when you hit that step goal. But 10,000 steps is roughly equivalent to 5 miles, a distance that many of us don’t have the time to meet daily.  Does this mean that we aren’t reaching our optimal level of health? Research suggests that exercise has benefits with far fewer steps. 

The 10,000 step goal originated in the 1960’s in Japan, when a company was trying to promote fitness after the 1964 Tokyo Olympic Games. This company created pedometers called Manpo-kei, which translates in English as “10,000-steps meter.” This was essentially a marketing tactic, but it took root over time. 

A study from 2019 put this number to the test and found that walking reduced mortality rates until about 7,500 steps a day, and then leveled off.  The CDC recommends 150 minutes of moderate-intensity exercise a week. This corresponds to just 30 minutes a day, 5 days a week. A brisk walk for 30 minutes is about 4,000 steps and has notable health benefits. 

Walking in any amount is good for your heart health and overall wellbeing. Physical activity can reduce your likelihood for many medical conditions, increase your mood and memory, improve your immunity, reduce stress levels, and much more. So, don’t worry too much about the specific number of steps. Go out and get a brisk 30-minute walk in today!

Antibody Testing For COVID-19

Image from


There’s a lot of talk about antibody levels as a measure of immunity against COVID-19 after infection or vaccination. This clashes with the knowledge that the immune system remembers prior invaders and can be reactivated if there is a new exposure. 

Antibodies are proteins the body uses to recognize foreign substances that should not be in your blood and flag down immune cells to destroy the invader. When a pathogen, such as a virus or bacterium, enters the body, the immune system is triggered to produce more antibodies. Vaccines often work by introducing an unharmful or artificial part of a pathogen into your body to make it produce antibodies. The level of antibodies may wane, but the B-type immune cells remember and can ramp up production of the invader returns. 

 Antibody tests detect whether a specific antibody is currently circulating in your body which is generally considered a marker of recent infection of immunization. Initially, COVID-19 antibody testing was used as one measure of whether or not a person had been infected with the virus. However, because it can take 1 to 3 weeks after the initial infection for antibodies to be measurable in your body, the tests are not used to detect a recent or active infection.  

The way antibody tests are often discussed in the media gives the impression that circulating antibodies are a measure of immunity against the virus. The real measure is whether or not your immune system is capable of mounting a new response to the virus, not whether a response is currently underway.  Circulating antibodies are a marker of an active immune response. 

So, antibody testing cannot tell you if your body is capable of producing an effective immune response against COVID-19. You may be able to mount a strong response even if you have no measurable antibodies in your blood.