Dear Mark: WiFi Effects on Health, Creatine and AGEs, and Introducing Solids

WiFiFor today’s edition of Dear Mark, we’ve got a two-parter followed by a question for Carrie. First, I discuss the effects of WiFi on health. Or, rather, I explore whether the potential effects of WiFi on health are worth fretting over or whether we should focus on more actionable factors that affect health. Second, I answer a three-part question about creatine and advanced glycation end products. Is there an interaction between supplementary creatine and AGE formation? Are the two contraindicated? Finally, my dear wife Carrie answers a question about introducing solids to a breastfed infant.

Let’s go:

Dear Mark,

I read an unsettling article explaining how our WiFi routers emit harmful radiation throughout the whole house. Is this a cause of concern do you think? Is it significant enough damage to affect my and my family members’ health?



You know, this is a tough one. I think there is evidence that WiFi signals have physiological effects. Epidemiology suggests a link between proximity to mobile phone base stations and increases in cancer and adverse neurobehavioral effects, even when exposure dosages were under the generally-recognized-as-safe limit. I’ve discussed the potential effect of laptops and cell phones on sperm health and motility before. There might be something there.

There’s also evidence that WiFi can improve health, though. A mouse model of Alzheimer’s disease experienced improved memory when exposed to 2.4 GHz WiFi. And there’s also lots of evidence that it has no effect, particularly on prenatal health and development.

My advice? Don’t worry too much. Worrying about the health effects of WiFi signals can actually increase the health effects of WiFi signals, even if it’s a sham signal!

WiFi is here to stay. Even now, you’re probably bathed in the stuff. If anything, its reach will only grow. You’ll be able to get full coverage while backpacking through the remotest jungles where you’ll stumble upon some untouched Amazonian tribe and upload your photos to Facebook. Heck, they might even already have Facebook accounts. “Remote” will probably cease being a useful descriptor altogether. Short of encasing your body in aluminum foil or moving to the wilderness, it will be impossible to escape WiFi entirely. The best thing we can do is optimize the aspects of life over which we do have control, like our exercise, our eating, our social relationships, our love life, our work life, and our sleep.

That said, getting away from it all (while you still can!) is definitely a good move from time to time, and for other reasons. Disconnect. Go out into nature where the signals are muted, if not absent altogether. These occasional (or more frequent) sojourns into natural solitude can be rejuvenating for the mind and body. Is it because you’re avoiding WiFi signals? Maybe, but I doubt it. Doesn’t really matter either way, though, if it works.

I did some research on creatine after reading your link love yesterday, and have some questions I hope you (as an athlete) can answer.

1. I’ve been giving us both L-carnosine because it breaks the bonds of AGEing. In wanting to prevent sugar from bonding to protein (muscle), thereby aging us, have I made a mistake?

2. Should I be using creatine instead, and not worry about AGE bonds?

3. How do I strike a balance between controlling AGE bonds and using muscles as a sugar-sink, or do I need to?


First, readers, recall that AGEs are advanced glycation end products. AGEs have been associated with inflammation, oxidative stress and aging.

1. Carnosine is a fairly effective inhibitor of AGE (advanced glycation endproducts) formation, especially those mediated by methylglyoxal. Although methylglyoxal’s wholly negative reputation might be unfounded (it does more than just glycate, actually plays an important physiological role, and may have chemotherapeutic effects), excessive AGE formation has been implicated in the negative effects of aging and many degenerative diseases. Luckily, simply by eating ample amounts of animal flesh – the only real dietary source of carnosine – you will obtain carnosine. In fact, vegetarians tend to have lower levels of carnosine (aging also lowers carnosine levels, which could be why many studies show that seniors benefit from significantly increasing protein intake over recommended levels). That’s not to say supplementation won’t help, just that you probably needn’t fret too much since you’re getting more from your diet than most and there’s still a lot about AGEs that we don’t quite know.

2. Creatine is fine. If anything, it will help against AGE formation! An in vitro study found that creatine actually inhibits glycation (PDF). That’s in addition to the beneficial effects on glucose control you already know about. Another study even found that creatine monohydrate (the most basic supplemental form) can improve recovery from nerve damage to muscles. Don’t expect a miracle cure, though.

3. I don’t think increased muscle glycogen levels and lower AGE formation are mutually exclusive. In a recent study of diabetic rats, using a cumin seed extract to improve blood glucose control also increased muscle and liver glycogen content while lowering AGE levels. Besides, stronger people (with bigger muscles and more glycogen) tend to live longer, and exercise (which necessitates glycogen repletion and increases glycogen storage capacity) is positively associated with longevity. There’s also an inverse relationship between muscle strength and AGE levels in the skin of adult men – the stronger you are, the fewer AGEs your skin has. All the evidence points toward muscle glycogen repletion being a good thing.

And now, let’s hear from Carrie on the topic of introducing solids:

Dear Mark (and Carrie),

I have a three-month-old, and since he’s starting to teeth and becoming a little bit interested in food (though he’s still far from trying to grab it from my fork or plate), I have been trying to find out what the best foods to start him with might be. All of my online research came back with “iron-fortified rice cereal”, or other similar results, and when I searched for an answer on your site, I came across an article that discusses feeding babies. However, mostly it talks about the benefits of breastfeeding, and what not to feed baby (with a brief “try more healthy brands, or make your own”), with only a very short few lines talking about what *to* start feeding baby. And so my question is: what would you suggest for good first foods, and what, if anything, should be avoided during those first couple of months of solid foods?

Respectfully yours,


First, I’ll speak from experience. I exclusively breastfed my kids until they were six months old. After that, I introduced solids while maintaining the breastfeeding, starting with cooked peas, carrots, and sweet potatoes. I wasn’t into processed foods, neither for myself nor our kids, so I made all their food instead of buying it. But I was still in the low-fat paradigm (lots of whole grains, fruits, veggies and low-fat dairy). It never crossed my mind to offer things like egg yolks or liver! They did great and have grown up to be healthy, happy (young) adults, but if I knew then what I knew now I probably would have introduced a few other foods as well.

Egg yolks are great. They’ve been shown to be a great way to increase iron stores in babies (PDF), who after the six month mark really start dipping into the iron reserves and require an outside source of it. Bonus points if you use DHA-enriched or pastured eggs, which are higher in nutrients and can increase the serum DHA levels of babies. Soft boil the eggs and either spoon the yolk direct into mouth, or mash with something like banana or sweet potato.

Liver’s another food I would have liked to have given my kids very early. It’s super high in folate, iron, and vitamin A, which are nutrients they need. Some people recommend giving it raw after being frozen for 14 days to eliminate pathogens, but I don’t know about that to be quite honest. I think lightly pan cooking it in some butter, coconut oil, or olive oil is just fine.

But mostly just let him decide based on what he’s drawn to on your plate. I think babies’ instincts should be respected. If you’re reading this blog, you’re probably eating a generally healthy diet, so I wouldn’t worry about just letting him eat what you’re eating. There aren’t too many restrictions. It’s generally accepted that you can feed babies food. Stay away from overly spicy stuff, but they don’t necessarily need bland, flavorless, boring food. Just start with little bites, little dabs of whatever food you’re offering, and see how they react. Babies tend to be super expressive with their faces. They’ll let you know when they don’t like something!

When you do offer starchy foods or fruits like sweet potatoes and bananas, consider pre-chewing them. Babies don’t make a ton of pancreatic amylase right off the bat, nor are they big chewers. Your saliva however does contain salivary amylase that can start the digestive process, survive passage into their guts, and make starch digestion easier for your baby. If you don’t want to chew the foods, be sure they are thoroughly cooked. Babies do make significant amounts of salivary amylase before pancreatic, too, so they’re not totally helpless as long as they gum the food (which they do!).

Regarding grains, there is some evidence that introducing too early (before 3 months) or “too late” (after around 7-8 months) can increase the risk of allergies or celiac in genetically susceptible kids. So if either of the baby’s parents have a history of celiac, gluten sensitivity, or other food intolerances, some people are recommending that he be introduced to cereal grains at around the six month mark. Other evidence suggests that waiting until 12 months is better. Could be that waiting even longer works even better. There’s not much evidence to say definitively either way. What’s my take on it? I’m not sure. The evidence is pretty interesting, if conflicting and unclear, despite our general anti-grain stance. I can conceivably see some benefit to giving a tiny bit of grain to an infant to prime them for later exposure. After all, it probably isn’t realistic to keep all grains and gluten from a kid for the rest of their lives. What happens when they go to a birthday party? A pizza joint with friends? Their lives are theirs, and they may choose to eat grains. If you do decide to introduce grains, make sure you’re still breastfeeding, which keeps the gut healthy and stocked full of beneficial, protective Bifidobacteria. A healthy gut appears to be key in preventing food intolerances from arising and promoting a healthy immune response to any food you may eat, and I think this is the most important factor (more so than when you introduce foods).

Well, that’s it for today, folks. Thanks for reading!

TAGS:  dear mark

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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