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Today’s Health Upgrade
All calories are not equal
Genetics and your lifespan
Foods are super: a very underrated fruit
On Our Radar
Why All Calories Are Not “Equal”
You've probably heard the argument before: "A calorie is a calorie." And while most people tend to misunderstand how this works — some foods influence energy balance, which means not all calories are the same — a new study takes it one step farther.
Research suggests that eating ultra-processed foods could lead to more fat gain than whole foods, even when calories and macronutrients are identical.
Scientists recruited healthy men for a tightly controlled feeding study where participants ate either an ultra-processed diet (77% of calories from packaged, industrial foods) or an unprocessed diet (66% from whole foods) for three weeks, then switched to the other diet. The nutrition plans were matched for total calories and macros.
Participants gained about 1 kg (roughly 2.2 pounds) more body fat on the ultra-processed diet, despite eating the same number of calories. Their LDL-to-HDL cholesterol ratio also worsened, a marker linked to cardiovascular risk. And blood tests revealed higher levels of phthalates, endocrine-disrupting chemicals that leach from food packaging.
The researchers believe processing itself changes how your body handles food. Ultra-processed foods tend to be easier to digest (meaning you absorb more energy), less satiating (so you may eat faster or want more), and they come with chemical baggage from packaging that can disrupt metabolism.
This does not mean you must avoid all ultra-processed foods. And you don't need to overhaul your entire diet overnight. Instead, start by identifying one or two ultra-processed staples and replace them with whole-food alternatives, like a handful of nuts instead of chips.
Small shifts add up, and your body composition may thank you even if your calorie count stays the same.
Longevity
How Much Do Genetics Determine Your Lifespan?
For years, researchers believed your DNA explained roughly 20 to 25 percent of how long you'd live. Some large-scale studies put as low as 6 percent. But a new study says they were looking at the wrong signal.
Research published in Science found that genetics accounts for about 55 percent of lifespan variation among people, more than double previous estimates.
Researchers analyzed three large twin datasets (including twins raised apart) and built mathematical models to strip out deaths caused by external factors like accidents, infections, and violence. Those types of deaths had created some misleading data.
Here's the clearest way to understand it: imagine identical twins with the same longevity genes. One dies of typhoid at 30. The other lives to 95. On paper, it looks like genetics barely matters. In reality, bad luck erased the genetic signal. When researchers removed that noise across all three datasets, the heritability estimate more than doubled.
That 55 percent figure now aligns with lifespan heritability in mice (38-55 percent) and with the average heritability of most complex human traits (around 49 percent). As the authors wrote, human lifespan is no longer the outlier it appeared to be.
Before you assume your DNA sets a ceiling, that's not what this means. Heritability is a population-level statistic. It quantifies the extent to which variation among people can be attributed to genetic differences. It doesn't tell any individual how long they'll live. Both the old and new estimates can be correct. They're measuring slightly different things.
Two things stand out from this research. First, the case for studying longevity genes just got significantly stronger. Second, roughly 45 percent of lifespan variation remains non-genetic—driven by environment, lifestyle, and what the researchers call "biological stochasticity," the inherent randomness of life.
At the end of the day, how you live, the choices you make, and the routines you create still have a significant impact on how long you live, even if you didn’t win the genetic lottery.
Foods Are Super
Pomegranate: The Fruit That Can Improve Your Bloodwork
Most "superfoods" earn the label from a single flashy study and a strong PR team. Pomegranate earned it the old-fashioned way, with a research resume that keeps growing.
Multiple meta-analyses show pomegranate reduces blood pressure, lowers key inflammatory markers, and contains compounds that may help your body clean up damaged cells and build stronger muscles.
A meta-analysis of 22 randomized controlled trials found pomegranate consumption lowered systolic blood pressure by roughly 8 mmHg. An earlier analysis confirmed the trend, showing a drop of about 5 mmHg.
The inflammation data is just as consistent. Across three separate meta-analyses (including one reviewing 33 randomized controlled trials), pomegranate supplementation significantly reduced CRP, IL-6, and TNF-alpha, three markers your doctor actually cares about when assessing long-term disease risk.
But the most interesting chapter is still being written. Pomegranate contains compounds called ellagitannins that your gut bacteria can convert into urolithin A, a molecule that triggers mitophagy, essentially a recycling program for damaged mitochondria. A four-month trial found urolithin A supplementation improved muscle strength by about 12%, along with better aerobic endurance and lower inflammation.
The catch: only about 40% of people make this conversion efficiently. Your gut microbiome determines whether you're a strong or weak producer. But even without the urolithin A benefit, pomegranate's polyphenols still improve blood pressure and inflammation.
About a cup of 100% pomegranate juice daily, or half a pomegranate's worth of arils tossed on a salad, yogurt, or into a smoothie, covers the effective dose used in most studies. Just check the label; you want juice, not sugar water with a pomegranate on the bottle.
Welcome To The Positive Corner
About Arnold’s Pump Club
We do things a bit differently here, starting with transparency.
The Content: All APC emails are researched, written, and fact-checked by the APC editors (see bottom of the email), with written contributions from Arnold (noted with “Arnold’s Corner”). Links take you to original studies (not second-hand sources).
Does AI play a role? Yes, in two places. Everything above is original content written by the APC team. The summaries below are AI-generated based on the human-written content above. We also use an AI tool to review our interpretations of the research and ensure scientific accuracy. We don’t assume AI is right, but we use technology to hold ourselves accountable.
Yes, we have partners (all clearly noted). Why? Because it allows these emails to remain free. We reach out to potential partners who offer ways to help you improve every day. The bar is set high, and to date, we have turned down millions in ad deals. (Example: we will not partner with any non-certified supplements or those without evidence in human trials). If we won’t buy the product, we won’t recommend it to you. And if there’s no evidence it works, then there’s no place for it here.
Better Today
Take any of these tips from today’s email and put them into action:
1. Same Calories, More Body Fat: What Ultra-Processed Foods Might Do That Whole Foods Don't
Participants in a controlled feeding study gained about 1 kg (2.2 lbs) more body fat eating ultra-processed foods compared to whole foods, even when total calories and macronutrients were identical. The ultra-processed diet also worsened LDL-to-HDL cholesterol ratios and increased blood levels of phthalates, endocrine-disrupting chemicals from food packaging. You don't need to overhaul everything. Start by swapping one or two packaged staples for whole-food alternatives.
2. Your Genes Control 55% of How Long You Live — But That's Not the Whole Story
Scientists found that genetics accounts for roughly 55% of lifespan variation, more than double the 20-25% previously estimated after correcting for deaths from accidents, infections, and other external factors that had masked the genetic signal. That still leaves about 45% attributable to environment, lifestyle, and biological randomness, meaning your daily choices carry significant weight regardless of your DNA.
3. The Research-Backed Case for Pomegranate: Blood Pressure, Inflammation, and a Cellular Cleanup (You've Never Heard Of)
Across multiple meta-analyses (including one reviewing 22 randomized controlled trials), pomegranate consumption lowered systolic blood pressure by roughly 8 mmHg and significantly reduced three key inflammatory markers (CRP, IL-6, TNF-alpha). Its compounds can also be converted by gut bacteria into urolithin A, a molecule that triggers mitophagy (recycling of damaged mitochondria) and improves muscle strength by about 12% in a four-month trial. About a cup of 100% pomegranate juice, or half a pomegranate, provides the effective dose.
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Publisher: Arnold Schwarzenegger
Editors-in-chief: Adam Bornstein and Daniel Ketchell
