By Daniel Gwartney, MD
If you have ever gotten stuck on an icy road, you know the frustration of hearing your tires spin while you get nowhere. Sometimes dieting feels like that – usually during your waking hours. Nearly everyone who wishes to lose weight has the desire and willpower to follow a diet and exercise program. Every January, gyms are filled with a lemming-like trail of new members who spend three weeks with a renewed vision of adding muscle and losing fat, only to disappear the remainder of the year. It isn’t laziness that accounts for the drop-off in most cases, rather it’s frustration over the lack of results.
It is only natural to seek out the best tools for achieving an improved physique that includes fat loss. One important aspect of weight loss is following the best diet. The low-fat versus low-carb argument has been waged for years; the latter is not bodybuilder friendly. Protein is an essential component of the diet; not only is it vital to health and function, it also aids in weight management through appetite suppression, promoting satiety and maintaining lean mass.1,2 However, is there a best protein source?
It is generally accepted that hydrolyzed whey protein, due to its rapid absorption and high branched-chain amino acid (BCAA) content, is the optimal anabolic (muscle building) protein.3 However, does that equate to it being the best protein in your diet for weight loss/fat loss? A growing research base suggests not.
Certainly, whey, casein and other proteins (e.g., egg, beef, pork, chicken, soy) can be part of a weight-loss diet. However, researchers have found (in rat studies) that the different proteins may include fractions that might support weight loss. These fractions, called bioactive peptides, are small proteins formed when the larger proteins are digested. Very little of these peptides actually get through the intestinal barrier to circulate through the bloodstream intact, so they have not been a focus of study in human nutrition. However, if the findings of a study published in the journal Metabolism Clinical and Experimental apply to human nutrition, then a highly relevant topic has been ignored.4
Heart-Healthy Protein Source
Researchers at Laval University (Quebec, Canada) had previously reported that rats fed cod protein were protected from developing type 2 diabetes as a consequence of eating a high-fat/high-sugar diet; no influence on bodyweight was involved.5 There was a reduction in C-reactive protein, a measure of inflammation that is associated with insulin resistance – the first step toward type 2 diabetes. Many other studies have shown that diets emphasizing fish as a significant protein source are heart healthy and protect against insulin resistance. However, the prevailing belief is that it is the omega-3 fatty acids in fish oil (DHA and EPA) that provide these health effects, not bioactive peptides in fish protein.6 To further investigate the potential benefits to be obtained from fish protein, separate from those arising from fish oil, the researchers provided groups of rats separate diets consisting of several different fish protein – each group received a different type of fish protein (bonito, herring, mackerel or salmon) of an equal number of calories. In addition to the fish protein, the rat food consisted of a high-fat, high-sugar (sucrose) formulation, the kind of diet that induced obesity, insulin resistance and promoted inflammation. The control diet was based upon casein, a type of milk protein. The fish protein was de-fatted so that there was no EPA or DHA (omega-3 fish oil).
With the absence of the omega-3 fish oils, it was somewhat surprising to note that all of the tested fish proteins reduced the inflammatory markers TNF-alpha and IL-6.4 High levels of these markers are associated with the metabolic syndrome. As the proteins were all de-fatted, these results suggest that some common peptide fraction has anti-inflammatory properties.
Given the common anti-inflammatory effect noted above, it was further surprising that all fish proteins did not react the same, providing the same result (or lack thereof), in reducing weight gain, visceral adipose (inner-belly fat) and improving insulin sensitivity. Of the four fish proteins tested in this study, only salmon protein resulted in less weight gain on the high-fat/high-sugar diet. After sacrificing the rats, it was discovered that the weight difference was due to less visceral fat; subcutaneous (under the skin) fat and brown fat (a specialized fat that creates heat from fat burning) were not different between the various groups. Liver weight was the same for all groups; no differences were seen in fasting glucose (blood sugar), insulin or triglycerides (fats in the blood).
An interesting test was performed, looking at the macrophages – white blood cells in the blood that release the early signaling inflammatory chemicals – and how they responded to a chemical challenge. The macrophages all acted as they normally would in the casein (milk protein) group, as well as all the fish protein groups EXCEPT the salmon protein group. Obesity is often referred to in academic journals as a chronic inflammatory state.7 Lowering macrophage activity in the visceral fat depot, and thus inflammation, may represent one of the mechanisms by which salmon protein results in healthier effects. Prior research has shown that the amino acid taurine, which is present in fish protein in high concentration, suppresses TNF-alpha and IL-6 in macrophages.8 However, these specific changes were not present in this study.
As the earlier study reported by this group, using cod protein, showed a decrease in insulin resistance, and as the salmon group had lower inflammatory markers and less visceral fat, the researchers were surprised to see that the salmon group did not have improvements as measured by an oral glucose tolerance test (OGTT). Doctors give patients an OGTT to determine whether they have the early stages of diabetes. It consists of drinking a super-sugary drink, then measuring how long the blood sugar, as well as insulin, is elevated. The OGTT is not a sensitive test, so the researchers utilized a more intensive test called the euglycemic-hyperinsulinemic clamp technique. This technique administers a steady amount of insulin that is higher than normal, and then the amount of sugar that needs to be delivered to maintain a normal blood sugar is measured. If the excess insulin can only dispose of a small amount of extra sugar, then that subject is not very insulin sensitive. If extra insulin results in a strong signal to the cells, and a greater amount of sugar is necessary to maintain a normal sugar, then that subject is very insulin sensitive.
Salmon: Greater Insulin Sensitivity
Given the direction of this conversation, it should not surprise anyone to read that the salmon protein resulted in greater insulin sensitivity than the other proteins.4 Though this was not seen in the OGTT, the clamp technique revealed that the body was more able to drive sugar into active cells. Another possibility is that the liver was more sensitive to the first-phase signaling of insulin, which shuts down gluconeogenesis – the production of sugar from ketones by the liver.
One last observation is extremely interesting, if such things interest you: the presence of a specific bioactive peptide in the salmon protein called salmon calcitonin. Calcitonin is a small protein (32 amino acids in length) hormone that is produced by numerous species, including humans. Human calcitonin is produced within specialized cells located in the thyroid, and serves to regulate ionized calcium concentration in the blood. It reduces the blood calcium level by reducing the absorption of calcium from the intestines, inhibiting calcium release from bones, and reducing the amount of calcium that is recovered by the kidneys from the urine. It is possible that by increasing the amount of calcium that remains in the intestines, calcitonin’s action might reduce the amount of fatty acids that are absorbed from food (and thus fat calories).
Salmon calcitonin is 40 times as strong as human calcitonin.4 It has been reported in earlier studies that calcitonin prevents the activation of macrophages, similar to what was seen in the rats fed salmon protein.9 This supports the theory that salmon calcitonin may be one of the active protein fractions responsible for the decreased inflammation noted in this study.
Calcitonin is structurally similar to another hormone called amylin, and can bind to and activate the amylin receptor. Amylin is involved in regulating bodyweight by increasing energy expenditure (the number of calories burned in a given amount of time). Salmon calcitonin has been shown to have the same effect when given as a specific treatment in animal studies. This adds another possible explanation as to why the rats fed salmon protein did not gain as much weight on the same diet. The other fish species used in this study have slight chemical differences in their respective calcitonin structures, and it has not been determined whether or not they can interact with the amylin receptor, possibly explaining the failure of those fish proteins to affect weight gain. Also, the blood levels of salmon calcitonin achieved through the diet may not be sufficient to have an effect on energy expenditure. Unfortunately, this was not measured in the study.
OK, another win for fat rats. Does this apply to humans? It is difficult to say. The salmon protein was pre-processed to make it suitable for rat pellets, and de-fatted. It was the sole protein source in the diet, which would not be economically feasible for many. The benefits of other protein sources would also be sacrificed.1 Also, rats were fed a terrible diet, and the salmon protein reduced the metabolic damage, but did not reduce subcutaneous fat. Would a “clean” diet see any benefit from salmon protein? Further, it remains to be seen whether the consumption of a reasonable amount of salmon by a human can raise salmon calcitonin sufficient to increase calorie burning. The human gut does not allow larger molecules to pass readily into the bloodstream. Would re-introducing the omega-3 fats improve or interfere with the fat loss? An earlier study suggests it would improve it. For those who want to build muscle, it is important to keep in mind that fish protein is relatively low in branched-chain amino acids. This raises questions of whether other protein sources would block the effects seen in diets where protein is exclusively sourced from salmon. People may experience mercury toxicity from fish-rich diets.
It is interesting, and there are certainly health benefits to eating more omega-3 rich fish. With the limited downside, when eaten in moderation, it appears that fish protein can aid in promoting health, insulin sensitivity, reducing inflammation and visceral fat. The best fish to consume appears to be salmon. Great news for rats, possibly good for humans, but bad news for the salmon.
1. Anderson GH, Luhovyy B, et al. Milk proteins in the regulation of body weight, satiety, food intake and glycemia. Nestle Nutr Workshop Ser Pediatr Program, 2011;67:147-59.
2. Frestedt JL, Zenk JL, et al. A whey-protein supplement increases fat loss and spares lean muscle in obese subjects: a randomized human clinical study. Nutr Metab (Lond), 2008 Mar 27;5:8.
3. Tang JE, Moore DR, et al. Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men. J Appl Physiol, 2009 Sep;107(3):987-92.
4. Pilon G, Ruzzin J, et al. Differential effects of various fish proteins in altering body weight, adiposity, inflammatory status, and insulin sensitivity in high-fat-fed rats. Metabolism, 2011 Aug;60(8):1122-30.
5. Lavigne C, Tremblay F, et al. Prevention of skeletal muscle insulin resistance by dietary cod protein in high fat-fed rats. Am J Physiol Endocrinol Metab, 2001 Jul;281(1):E62-71.
6. Tai CC, Ding ST. N-3 polyunsaturated fatty acids regulate lipid metabolism through several inflammation mediators: mechanisms and implications for obesity prevention. J Nutr Biochem, 2010 May;21(5):357-63.
7. Rocha VZ, Folco EJ. Inflammatory concepts of obesity. Int J Inflam, 2011;2011:529061.
8. Schuller-Levis GB, Park E. Taurine: new implications for an old amino acid. FEMS Microbiol Lett, 2003 Sep 26;226(2):195-202.
Have you tried this NEW workout plan that everyone is talking about?
A Low-Impact Resistance Band Workout for Your Upper Body
When it comes to workout tools, resistance bands are often under-appreciated. These stretchy, looped devices offer a ton of benefits—including effective, low-impact strengthening—but in many gyms they take a backseat to heftier equipment like dumbbells, kettlebells, and barbells.
But not today. We've got a 25-minute Sweat with SELF workout that gives resistance band exercises the spotlight they deserve. The routine—created and led by Taylor and Justin Norris, cofounders of the LIT Method—features nine resistance band exercises that will seriously engage your muscles and get your heart pumping without straining your joints. You can easily do this workout at home and scale it up or down to match your fitness level.
Yet another perk of this workout: It emphasizes your upper body—particularly the back, shoulders, and arms. Strengthening these key areas can help anyone improve their posture, as SELF previously reported.
Ready to try this sweaty program? First, make sure it's safe for you. If you're injured or have joint pain, check in with a professional to determine whether a routine like this is a good idea.
Once you're given the OK for this workout, grab a mat, water bottle, and resistance band. (If you're new to resistance bands or to working out in general, start with a light resistance band. As you progress, you can amp up the intensity with a heavier resistance band.) Check out the video below. Or, keep scrolling to get detailed resistance band exercise directions and GIFs of each move.
Start with the dynamic warm-up. Do each exercise for 60 seconds with no rest between movements. When you're done, rest for 30 seconds.
Next, move on to the circuits. There are 3 circuits with 3 moves each, and all moves use the resistance band unless otherwise noted. Do each move for 60 seconds with little to no rest. (It's okay to take 5 to 10 seconds between each move to transition to the next.) At the end of the circuit, rest for 30 seconds. Do each circuit 2 times before moving to the next circuit.
- Bodyweight Upright Row x 60 seconds
- Jab x 60 seconds
- Side Stretch x 60 seconds
- Squat to Biceps Curl x 60 seconds
- Squat to Row x 60 seconds
- Standing Crunch x 60 seconds
Rest for 30 seconds. Repeat the circuit once more.
- Bent-Over Row x 60 seconds
- Biceps Curl x 60 seconds
- Triceps Kickback x 60 seconds
Rest for 30 seconds. Repeat the circuit once more.
- Seated Row x 60 seconds
- Seated Biceps Curl x 60 seconds
- Seated Static Hold x 60 seconds
Rest for 30 seconds. Repeat the circuit once more.
Fitness / Workouts
Cullen Jones’s Success Story
As a kid growing up in New Jersey, I always watched the Olympics. And in 2006, after swimming for North Carolina State University, I found myself in the pool alongside Michael Phelps at the Pan Pacific Championships, where he beat me by 1/10th of a second. By 2007 I had made the U.S. World Championship team.
It was the next year, in 2008, that I found myself in a rut and decided to do something unorthodox. If I was going to make the Olympic team, I knew I needed a change.
I called the coach for the national team, and he told me I needed to train with the Olympic-level coach in Charlotte, N.C., about three hours away from where I was living in Raleigh. It was nearly midnight when I finished that call, and I left that night without telling my coach at N.C. State, who thankfully understood.
At practice with my new coach the next morning, I realized I was rusty — my metabolism had slowed down and I wasn’t eating as healthy as I should have been. So, I buckled in for a whirlwind of training, revamped my eating, started lifting weights, and ramped up important skills like visualization and staying present in the moment.
Two months after arriving in Charlotte, I went to the Olympic trials, made the team, and went on to win a gold medal as part of the 400 free relay team.
The first thing I did was thank my coach at N.C. State for empowering me to do what was best for me and to be the best athlete I could be. Given my childhood experiences in the pool, winning a gold medal wasn’t something anyone could have predicted — especially since I nearly drowned at age 5.
My Swimming Scare
My dad has always been my mentor, and I always wanted to follow in his footsteps and do as he did. So, when he told me he was going down the waterslide at Dorney Park and Wildwater Kingdom in Allentown, Penn., I was right behind him.
At the time, I was 5 years old, but I still remember what my dad had told me: “Whatever you do, don’t let go of the inner tube.” In fact, he said it twice.
My dad went first. Then, almost as quickly as my ride had begun, I hit the water and flipped upside down, unable to pull myself back up. Time had to have passed slowly . . . 29, 30, 31, 32. I was stuck underwater for 30 to 35 seconds — an amount of time that can cause brain damage in children.
The next thing I knew, I had been rescued by a lifeguard. And I had one question: What ride are we going on next?
My mother (who had not been far behind me on the waterslide and subsequently nearly drowned herself while trying to save me) was the one to immediately insist I take swimming lessons. Looking back, I realize how bold a decision that was; it would have been so easy for her as a protective mother to swear off swimming altogether.
I absolutely bombed my first lesson. I cried. I hated being in the water, and I told my mom I needed a new teacher. It took five different teachers until I felt comfortable — and by that time I was 8 years old. Little did I know I was already building the empathy I would need to later teach others to swim.
Around the same time, my passion and competitive drive for swimming began. I remember watching other kids racing, and I was drawn to it immediately. In my head, I believed I could beat them.
Did that happen? No. At the time, it may have been hard to believe that I would eventually be a four-time Olympic medalist and the second African American in history to win an Olympic gold medal in swimming. But I was having fun, and it was an outlet where I could control my progression. So I kept swimming.
Creating Positive Change
I swam throughout high school, even though most of my classmates — the majority of whom were Black or Latinx — played football or basketball, or ran track. I would often end up in the weight room at the same time as the school’s basketball team, many of whom didn’t necessarily see swimmers as athletes. I always took joy in surprising them with my bench-press and pull-up skills.
Many of my classmates also didn’t see a place for themselves in swimming, and during my time training for the Olympics, I had been so focused on representing my team and competing that I hadn’t processed the fact that I was going to be a role model for young swimmers of color.
I was living in New York City at the time, and it wasn’t until I got back home that it really hit me. When I was growing up, no Olympic swimmers looked like me, and now I was able to show young people what was possible.
I believe that creating change and making the sport more inclusive starts at the grassroots level. There is a stereotype that Black people don’t swim, which is rooted in the very real fact that we were not always allowed access to public pools. So, when you’re teaching a person of color, you’re often reprogramming their mindset — and even the mindset of their family.
Looking Toward the Future
Swimming and fitness are still a huge part of my life. Especially during the pandemic, I’ve realized how essential activity is to my well-being when the world can be so unpredictable.
I’m currently working with Speedo as the philanthropic sales manager; I lead its fundraising initiatives, enhance its relationship with grassroots teams, and develop its community-support strategy.
I’ve also been working with the USA Swimming Foundation’s Make a Splash initiative for the past 12 years, teaching others, especially children of color, how to swim. The program promotes water safety by providing free swimming lessons to children from disadvantaged communities. We’ve helped reduce the number of African Americans with little or no swimming ability from 70 percent in 2007 to 64 percent today.
Along with this work, I spend a good chunk of time at events and colleges speaking about overcoming challenges and the powerful and transferable life skills common to athletes, like growth mindset, time management, and motivation.
I want to work hard now so I can spend as much time as possible with my family in the future. Also — and I want this to be in print, so I hold myself to it! — I want to travel for my 40th birthday, be fit, and look great in a black T-shirt.
Swimming is for everyone, and it’s an essential life skill. This is the same approach I take with my 2-year-old son, Ayvn — he just needs to learn to swim. He doesn’t need to be an Olympic athlete; I just want to know that when we’re near water he’ll be safe.
Cullen’s Top 3 Success Strategies
- “Strive for perfection but settle for first place.” It’s easy to beat yourself up, but remember to give yourself some grace. Work hard and be proud that you laid it all out there.
- Focus on your goal. When you swim, there might not always be people who look like you or who you can relate to, he says. But if you keep your focus on your progression, you’ll grow as a person and you might even change your life.
- Know when to be relentless. Cullen’s mom insisted he learn to swim. Not only was it an extremely important life skill, but it was the reason he became a four-time Olympic medalist.
Tell Us Your Story! Have a transformational healthy-living tale of your own? Share it with us!
This article originally appeared as “Welcome to the Water” in the June 2021 issue of Experience Life.
Have you tried this NEW workout plan that everyone is talking about?
Moving for Mental Health
As a freshman in high school, Lindsay Byrd didn’t recognize her anxiety for what it was. The teen — and aspiring surgeon — had always had perfectionist tendencies, so she thought it was natural to feel stressed about academics and her GPA. She knew she needed stellar grades to achieve her goals.
But when she started approaching her teachers to discuss assignments they’d graded and scores she’d received, one of her teachers took notice. She scheduled a meeting with Lindsay’s parents to discuss her concerns and went so far as to say that she didn’t think Lindsay would make it beyond her early 20s if she continued to be so stressed over school.
Lindsay and her parents were caught off guard by the teacher’s concerns, but they listened and took immediate action. She began seeing a therapist, who diagnosed her with anxiety and depression. Other than school-related stress, Lindsay can’t pinpoint anything else that might have caused these issues for her. “I think it’s important to note there doesn’t have do be a particular issue or trauma or wound for mental illness to affect people.”
She attended therapy regularly and eventually began taking medications. These measures were helpful and she felt OK for a while. But then Lindsay started to notice some worrying trends during her sophomore year.
“I always had highs and lows, but I really started to notice a lot of lows,” she recalls. “To the point where I couldn’t even think about the highs because everything was just a low. I felt like my brain was sick — I was constantly sad.”
The issue came to a head when Lindsay’s depression progressed to the point where she stopped caring about school. “That was when I realized something was drastically wrong. School was my love, and I just didn’t want to go anymore.” She knew that something needed to change.
Physical fitness had never been a top priority for Lindsay. Though she’d joined the dance team in middle school, she’d largely strayed away from sports after eighth grade. Her schoolwork became her focus, and it didn’t leave much time for her to worry about being active.
In 2020, Lindsay decided to sign up for a membership at Life Time. Her older brothers had been working out for several years, and she’d seen how integral fitness was in their lives. She thought if it worked for them, maybe it was worth a try — though she had no real desire to workout.
To get motivated, Lindsay made a deal with herself: After every workout she completed, she’d let herself relax in the jacuzzi.
To get started, Lindsay initially worked with a personal trainer, who showed her how to do squats and other strength exercises. She even started running on the treadmill, something she never thought she’d do. She started with small increments — just five minutes — and slowly added more time to her runs. Soon enough, she was hitting a mile.
She was blown away — and was also hooked. “Once you start working out, you don’t even have to think about it anymore. I started working out every day, and then it just became a habit, and I didn’t even need to go to the jacuzzi anymore.”
As Lindsay established her routine, it didn’t take long before she began to notice the effects it was having on her mental health. She remembers being motivated by the feeling of her body when it was sore, which indicated progress. And she thrived on the sense of accomplishment she gained from her physical progress — coupled with the serotonin release from her workouts.
“I’ve always loved to feel proud of something that I did,” says Lindsay. “When I started to feel accomplishment, and to feel like I could see progress, that was when I really got the boost. It was like ‘OK, Lindsay, you did it!’”
Lindsay’s fitness gains inspired her to focus on her eating habits, too — she didn’t want her diet to hinder her progress. So she started taking more notice of what she was using to fuel her body. “When I went to the grocery store, instead of grabbing snacks from the chip aisle, I’d grab them from the granola and peanut aisle,” Lindsay recalls. “When I started eating better in addition to working out, I started to have more energy on a daily basis.”
Focusing on a Bright Future
After personally experiencing the mental, emotional, and physical benefits of working out, Lindsay, now 18 and just weeks away from her high-school graduation, notes that it was hard when fitness centers closed down due to COVID in 2020. She did what she could to maintain a routine by going on brisk walks outside and doing some at-home strength training — but she realized quickly how important Life Time had become to her.
And as soon as the health club reopened, she jumped back into her routine, making up for lost time.
Now, as she looks back at her mental-health journey (so far), Lindsay wishes that one of her doctors or a therapist would have recommended physical activity as part of her recovery plan. She acknowledges the value of therapy and medication, but for her, exercise turned out to be her most important tool.
“Little did I know that my mental health would be impacted more than my body,” she says. “Even after a 5-minute run, both my body and mind feel better.”
More importantly, Lindsay’s experience has encouraged her to look outward. Having seen how much her well-being improved after adopting a fitness routine, Lindsay would love to see other people — particularly those struggling with mental-health issues — try to incorporate fitness and movement into their lives.
“I think that doctors forget to tell you that, yes, the medicine might work, yes, the therapy might work, but one other thing that can really change your mental well-being is focusing on your physical body,” Lindsay says. “If you focus on nutrition and getting active, the mental well-being often benefits, too. My hope is that people will just give it a try. You know, see how their brain feels after a little bit of working out and a little bit of good food.”