TODAY'S AJENDA #55

Meet Dr. Adam B. Cohen. He’s the Director of Sports Medicine at OrthoManhattan and a board-certified orthopedic surgeon with decades of experience in arthroscopic, robotic, and knee and shoulder surgery. 

Dr. Cohen is here to demystify your bone health—from the worst things you could do to your bones to whether collagen supplements actually help your joints. His insights might (literally) change the way you walk through life. 

Ready? Let’s dive in: 

1. Can I do squats and lunges if I have “bad knees”? 

It depends on what you mean by “bad knees.”  

Knee pain can stem from many causes. Arthritis. Meniscus tears. Ligament damage. It could even be pain originating from your hips or ankles! That’s why getting a clear diagnosis is the first step before deciding which exercises are right for you. 

That said, squats and lunges aren’t inherently bad for knees. When done right, they actually strengthen the muscles protecting the knee joint, including the quads, hamstrings, glutes, and calves. 

But not all knees tolerate these exercises. 

Squats can stress the knee joint, while lunges put a high load on the front of the knee—especially if your knee travels too far forward or your hips aren’t quite in control. 

For those with patellofemoral arthritis, I suggest modifying your lunge depth, limiting how far your knee travels forward, or using support. And in more painful cases? It might be best to skip these exercises altogether.  

Quick Tips: 

• Modify when needed – Try partial squats or swap in lower-load alternatives like step-ups or wall sits.

• Strengthen around the joint – Emphasize hip and core strengthening to offload stress on the knees.

• Listen to your body – Discomfort in the muscles is normal; sharp or lingering joint pain is a sign to back off or adjust.

2. What are the best and worst exercises for knees for women over 50?

It’s not about your age—it’s about your knee’s condition. I’ve helped 70-year-olds train for marathons and seen 30-somethings needing joint replacements. Age is just one part of the picture: It’s joint health that matters most.

Before we dive into exercises, it helps to understand how your joint cartilage functions. This smooth, cushioning surface at the end of your bones is maintained by cells called chondrocytes. 

These cells thrive under moderate physical stress, which helps maintain cartilage health. But too much stress can harm them—and damaged chondrocytes are vulnerable to further breakdown.  

That’s why the right kind—and right amount—of movement is so important.

Best Exercises

Low-impact exercises that strengthen the muscles supporting the knee are generally the safest and most effective. Some of my go-to options include:

• Swimming or water aerobics 

• Step-ups (using a low step)  

• Stationary biking  

• Pilates  

• Tai Chi  

• Yoga 

Exercises to Be Cautious With 

Certain movements can increase stress on the knees and are best avoided if you’re dealing with pain, arthritis, or prior injuries. They include: 

• Deep squats or lunges with heavy weights  

• Heavy leg extensions on gym machines  

• Running or jumping on hard surfaces  

• Deep-flexion yoga poses  

3) What are your thoughts on glucosamine for joint pain?

Glucosamine occurs naturally in healthy cartilage and is popular for managing osteoarthritis symptoms, a degenerative joint condition where joint cushioning gradually disintegrates. 

According to the American Academy of Orthopaedic Surgeons (AAOS), glucosamine may be helpful in reducing pain and improving function in patients with mild to moderate knee osteoarthritis, but the evidence is inconsistent and limited.

For that reason, I don’t routinely recommend it. Not because it’s unsafe, but because we simply don’t have strong enough data. 

4) Does collagen help my joints as well as my hair and skin?

Collagen is a major component of cartilage, the connective tissue that cushions your joints. The theory is that if you consume collagen peptides, your body might use them to help repair or strengthen joint cartilage. 

It’s a compelling idea. But when it comes to real-world evidence—especially for those with osteoarthritis—the picture is murky.

There’s limited research on collagen peptides for osteoarthritis. Most studies focus only on pain relief, such as one 2023 meta-analysis that found that collagen supplements led to modest pain relief compared to placebo (Journal of Orthopaedic Surgery and Research, Zhang et al). 

However, there’s not much research on whether the supplements actually improve cartilage, slow disease progression, or reduce long-term arthritis risk. 

That’s an important distinction. To put it in perspective: Tylenol can reduce pain, but that’s different from saying it “helps” your joints.

More rigorous, long-term studies are needed to figure out whether collagen can actually protect cartilage or change the course of osteoarthritis—not just reduce the symptoms.

5) What’s the worst thing people do to their bones? 

Common culprits include:

• Drinking too many cola-type sodas. They’re full of phosphoric acid, which likely interferes with calcium absorption.

• Excessive caffeine or alcohol consumption. Both of these decrease calcium absorption and increase calcium loss.

• Smoking. This bad habit disrupts your body’s ability to effectively use calcium and vitamin D.

• Avoiding sunlight or not supplementing vitamin D. Both of these lead to inadequate calcium absorption.

• Under-exercising. This deprives your bones of the necessary stress to build and maintain strength.

Fortunately, each of these habits can be improved through diet, exercise, lifestyle changes, and targeted supplementation.

I’ve been hearing from many of you who absolutely love the Alice Mushrooms Nightcap* for better sleep. But in all the hubbub I neglected to tell you about Alice’s other product: Brainstorm! 

“Mushroom what?” For those of you who are new to Ajenda, about a year ago, I went to an event hosted by Alice Mushroom’s brilliant founders, Lindsay Goodstein and Charlotte Cruze. 

I’ll admit—I was intrigued (and a smidge skeptical) about mushrooms and their health benefits. So I struck up a conversation with Lindsay and Charlotte. Their approach to natural wellness immediately resonated with me as a nutritionist and physician who strongly believes in the power of food. 

But as with anything, I had to test them out myself.  

A year later, I can now say Alice Chocolates have truly made a difference. 

For those wondering: Alice Chocolates are not psychedelic mushrooms! They don’t contain psilocybin or other hallucinogenic compounds. They’re formulated with functional mushrooms at non-pharmacological doses, meaning they don’t contain doses that would cause drug-like effects. 

I was so impressed with their science-backed ingredients that I not only became Alice Mushroom’s medical and nutritional advisor, but also an investor (which is how I’m able to get my subscribers a special discounted rate). 

That level of commitment should tell you just how much I believe in them! Now, I have Alice Chocolates almost every day. 

In the afternoons—or before a workout—I’ll have a square of Brainstorm for a natural energy and focus boost. Then, I have one square of Nightcap as a pre-bedtime ritual.  

While I’ve covered the science behind Nightcap works, I haven’t yet done a deep dive on Brainstorm. 

Let’s do that now, shall we? 

What’s Actually In This Product? 

Lion's Mane Mushroom 

These large, white, shaggy mushrooms resemble a lion’s mane (hence the name!) and are brimming with bioactive compounds (such as hericenones and erinacines) known to support nerve growth factor (NGF). 

Plus? A study published in Phytotherapy Research found that older adults with mild cognitive impairment taking Lion’s Mane for 16 weeks showed significantly improved cognitive function scores. (Mori et al., 2009).

Cordyceps 

Cordyceps, also known as ‘caterpillar fungus,’ have a long history in traditional Chinese medicine as energy boosters—and modern research backs this up. A study found that Cordyceps mushrooms supplements can improve people's ability to handle high-intensity exercise after just seven days. 

And after three weeks? Participants saw significant improvement in maximal oxygen consumption, time to exhaustion, and ventilatory threshold. (Hirsch et al., 2017). 

Phosphatidylserine (PS)  

Phosphatidylserine is a fatty substance that protects nerve cells in your brain. It’s essential for a healthy brain—it supports cognitive functions such as memory, attention, and mental clarity. 

Studies show phosphatidylserine supplementation can boost focus, slow cognitive decline, and may decrease stress hormones like cortisol. The result is clearer cognitive energy and sustained concentration (Glade & Smith, 2015). 

Guarana  

Last up is Guarana, a caffeinated Brazilian berry packed with theobromine and antioxidants that provides a smooth flow of energy.

However, unlike your morning coffee, guarana releases caffeine slowly. That means steady energy without the jitters and crash of energy (Scholey & Haskell, 2008). 

And guarana delivers more than just energy. Evidence published in Journal of Psychopharmacology found that guarana can enhance cognitive performance and reduce mental fatigue (Haskell et al., 2007).

A Word on Safety 

These chocolate squares are tiny, but they contain ingredients with documented physiological effects. It’s important to be aware of the risks if you consume any of these ingredients individually in high doses or as a separate supplement. 

Let’s dive into the details of each: 

1. Lion’s Mane Mushroom

Lion’s Mane is generally safe and well-tolerated by most, but potential risks include gastrointestinal upset (gas, constipation) and the rare chance of an allergic reaction. There’s also limited data on long-term safety, especially at higher doses. And be cautious if you’re taking blood-thinning medications as Lion’s Mane may interact with anticoagulants. 

2. Cordyceps

Cordyceps is typically safe short-term in recommended doses, but it can upset your stomach or affect your immune system, especially if you have an autoimmune condition. It could also interact with anticoagulants, immunosuppressants, or diabetes medications because of its hypoglycemic effects.

3. Phosphatidylserine

Phosphatidylserine is well-studied and considered safe. But it can sometimes cause mild bloating or gas, and taking it late in the day might affect your sleep. It could also boost the effects of cognitive medication—so if you’re on Alzheimer’s drugs or anticholinergics, consult your healthcare provider!

4. Guarana

Guarana is safe in moderation, but since it contains caffeine, be careful not to overdo it. Too much caffeine can cause anxiety, insomnia, restlessness, or a racing heart. High doses could also raise your blood pressure or trigger arrhythmias. It’s best to avoid Guarana with antidepressants or medications affecting cardiovascular function.

Ready for an instant boost of energy and focus–all in one mouthwatering supplement? Use the code AJENDA20 for 20% off your order!

The gold standard for protein comes from whole food (lentils, eggs, salmon, turkey, etc). That’s the ideal…but life has a way of throwing curveballs. Between time constraints, travel, and an empty fridge staring back at you, hitting your protein target can feel impossible. 

That’s where protein powders come in. If you’ve been following me on Instagram (@drjashton), you know I’m a fan of adding protein powder to smoothies when I’m not on track to hit my daily protein or fiber goals. 

But I still get a ton of questions on their efficacy and safety. 

Let me be clear: I am strongly pro protein powder! They’re popular for a reason—they can support muscle growth, weight management, and overall nutrition, all in one convenient scoop. 

However, they carry both benefits and potential risks. 

The Pros of Protein Powder 

• Convenient and Effective: If you’re struggling to hit your protein goals through whole foods alone, protein powder can be a lifesaver. It’s especially useful for athletes or those with dietary restrictions. 

• Boosts Muscle Growth and Recovery: Exercising a lot? Hitting the gym? Protein powder can help your muscles recover and grow faster after a workout (Phillips, S. M. Nutrition & Metabolism, 2016). 

• Weight Management: Protein powder can help control appetite, boost your metabolism, and support weight loss if you’re decreasing your calorie intake elsewhere (Leidy et al., The American Journal of Clinical Nutrition, 2015).   

The Cons of Protein Powder 

• Nutritionally Limited: Protein powder doesn’t have the B3 and B6 vitamins found in chicken, or the calcium and antioxidants in Greek yogurt. Whole foods offer a complete nutritional package that powders can’t match. 

• Digestive Issues: In some cases, protein powder can trigger gastrointestinal discomfort, such as bloating or gas. 

One More Concern We Should Talk About 

The biggest concern when it comes to protein powders is contamination by heavy metals like arsenic, lead, mercury, and cadmium. 

This isn’t some conspiracy: studies have found “detectable concentrations” of these metals in many commercial products (Consumer Reports, 2018; Clean Label Project, 2018). Long-term consumption of these metals can lead to kidney damage, neurological problems, and increased cancer risk. 

But you can mitigate this risk. Choose a protein powder certified by reputable third-party testing organizations, such as NSF International or Informed Choice, and opt for whole food sources of protein when you can. 

As for me? I do blood tests 1-2 times a year to check for heavy metal levels. While insurance doesn't cover it, the out-of-pocket cost is well worth the peace of mind (and body!). 

Thank you @mariarodz3 for the question!

Did you enjoy Today’s Ajenda? It would mean the world if you left us a testimonial!

ABOUT DR. JEN

In her former roles as chief medical correspondent for ABC News and on-air cohost of “GMA3: What You Need to Know,” Dr. Jennifer Ashton—"Dr. Jen”—has shared the latest health news and information with millions of viewers nationwide. As an OB-GYN, nutritionist, and board-certified obesity medicine specialist, she is passionate about promoting optimal health for “the whole woman.” She has authored several books, including the national best-seller, The Self-Care Solution: A Year of Becoming Happier, Healthier & Fitter—One Month at a Time. And she has gone through menopause…

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