Nutrition and Diet: What the Science Says

Last updated: October 21, 2026.

This guide collects the nutrition studies covered on Nexo Science, grouped by the questions people actually ask. Each link goes to a full article about one peer-reviewed paper: who was studied, what was found and where the limits are.

Most of these papers are meta-analyses or large cohorts. Many find associations, which are not proof of cause, and none of this replaces advice from your doctor or a dietitian. We update this page as new studies come out.

Eating patterns: the Mediterranean diet and beyond

• Is the Mediterranean Diet the Secret Not Just to Living Longer, But to Living Better? Science Says Yes
  A large analysis links the Mediterranean diet to a better quality of life, not just a longer one.
• Following a Mediterranean Diet Is Linked to a 30% Lower Risk of Alzheimer’s, a New Meta-Analysis Finds
  A meta-analysis ties close adherence to about a 30% lower risk of Alzheimer's.
• Going Vegetarian or Vegan Could Lower Your Cholesterol in Weeks, a Review of 30 Trials Finds
  A review of 30 trials found that vegetarian and vegan diets lowered cholesterol within weeks.
• Legumes in Asia versus legumes in the West: why the same food stops buying you time
  Legumes were tied to longer life in some regions but not in others, and the study looks at why.
• There’s an Exact Amount of Ultra-Processed Food That Spikes Your Diabetes Risk: It’s 300 Grams a Day
  Diabetes risk climbed past a specific daily amount of ultra-processed food, about 300 grams.
• 90 Grams of Whole Grain a Day Are Linked to Up to 20% Less Risk of Dying Early
  About 90 grams of whole grains a day was linked to up to 20% lower risk of dying early.
• More Fruit and Vegetables in Kids’ Diets Could Mean Less Wheezing
  Children who ate more fruit and vegetables had less wheezing.

Meat, protein and muscle

• The Evidence Tying Red Meat to an Early Death Is Weaker Than It Looks
  The link between red meat and early death is weaker than the headlines suggest.
• Can Small Meat Swaps Actually Lower Your Colon Cancer Risk?
  Whether small swaps away from meat change colon cancer risk.
• Is a High-Protein Diet Bad for Your Heart? Data From Half a Million People Say No
  In half a million people, high-protein diets were not linked to worse heart outcomes.
• Plant Protein Falls Slightly Short of Animal Protein for Building Muscle
  Animal protein built slightly more muscle than plant protein, mostly in adults under 60.
• Creatine Helps Postmenopausal Women Gain Muscle and Strength, According to the Largest Meta-Analysis Ever Done
  Creatine helped postmenopausal women gain muscle and strength.

Fats, dairy, nuts and fish

• Does Eating Less Saturated Fat Actually Help You Live Longer?
  What the evidence says about cutting saturated fat and living longer.
• This Plant Fat in Walnuts and Flaxseed Could Cut Your Risk of Fatal Heart Disease by Up to 20%
  ALA, the plant omega-3 in walnuts and flaxseed, was linked to up to 20% lower risk of fatal heart disease.
• Adding Olive Oil to an Already Healthy Diet Lowered Cholesterol Less Than Leaving It Out
  Adding olive oil to an already healthy diet lowered cholesterol less than leaving it out.
• Could Cheese Be the Dairy Your Heart Actually Wants?
  Cheese may be the dairy food that is kindest to the heart.
• Can Eating Nuts Every Week Actually Keep Depression Away?
  Whether eating nuts every week is linked to less depression.
• Multiple Sclerosis: Why Fish Might Slow Down Disability
  Eating fish and slower disability in multiple sclerosis.

Salt, sugar, coffee and alcohol

• If You’re a Woman, a Salty Diet May Be Riskier for Your Heart
  A salty diet may raise heart risk more in women than in men.
• Diet Soda Isn’t the Safe Swap: Sweetened Drinks of Any Kind Raise Heart Risk
  Sweetened drinks of any kind, diet soda included, were linked to higher heart risk.
• Diet Soda Isn’t as Harmless as It’s Marketed, But It Still Beats the Alternative
  Diet soda is not harmless, but it still compares well with sugary drinks.
• Why Does the Same Cup of Coffee Hit Some People So Much Harder?
  Why the same cup of coffee hits some people much harder than others.
• Matcha Left Memory Unchanged, But Changed Something Else in the Brain
  Matcha left memory unchanged but changed something else in the brain.
• Hydration and Diabetes: A Link Hiding in Plain Sight
  The overlooked link between hydration and diabetes.
• Moderate Drinking Could Lower Your Alzheimer’s Risk, According to the Largest Meta-Analysis Ever Done on Alcohol and Dementia
  Moderate drinking and Alzheimer's risk in a large meta-analysis.
• Can Your Urine Reveal Whether Wine Is Actually Good for Your Heart?
  What urine markers reveal about wine and heart health.
• This Is What Happens to Cancer Risk When Smoking Meets Drinking
  How cancer risk changes when smoking and drinking combine.

Weight, fasting and belly fat

• Intermittent Fasting Doesn’t Beat Simply Eating Less, According to the Most Complete Analysis Ever Done
  Intermittent fasting did not beat simply eating fewer calories.
• Stopping Ozempic Has a Very Concrete Price: You Regain Weight at a Rate of 0.4 Kilograms a Month, According to the Largest Analysis Ever Done
  After stopping Ozempic, weight comes back at about 0.4 kg a month.
• Diet or Exercise: Which One Actually Melts Away Dangerous Belly Fat?
  Diet or exercise: which one reduces dangerous visceral belly fat more.
• Probiotics and Belly Fat: A Small Win With Real Limits
  Probiotics and belly fat: a small effect with real limits.

Gut health, fiber and fermented foods

• Fiber From Food vs. Fiber Pills: Only One Seems to Help Your Mood
  Fiber from food, not from pills, was linked to a better mood.
• Fiber versus probiotics: only one was linked to longer survival on cancer immunotherapy
  On cancer immunotherapy, fiber, not probiotics, was linked to longer survival.
• Here’s What Probiotics Might Actually Be Doing to Your Memory
  What probiotics may be doing to memory.
• Eat More Fermented Foods, and Your Blood Pressure Might Notice
  Fermented foods and blood pressure.
• Could the Bacteria in Your Gut Be Quietly Helping Your Thyroid?
  Gut bacteria and the thyroid.
• Fecal Transplants Were Tested as a Parkinson’s Treatment: Here’s What the Science Has Found So Far
  What fecal transplants have shown so far as a Parkinson's treatment.

Vitamins, minerals and supplements

• Here’s What Daily Multivitamins Really Do to Your Lifespan
  What daily multivitamins do, and do not do, for lifespan.
• Calcium and Vitamin D Don’t Prevent Fractures or Falls, According to the Largest Meta-Analysis Ever Done
  Calcium and vitamin D did not prevent fractures or falls.
• Vitamin D Might Matter More for Your Brain Than Your Bones
  Vitamin D may matter more for the brain than for the bones.
• Here’s What May Happen to Your Brain When Magnesium Runs Too Low or Too High
  What happens in the brain when magnesium runs too low or too high.
• Can an Iron Pill Actually Fix an Exhausted Athlete?
  Whether an iron pill can fix an exhausted athlete.
• Healthy Prostates Hoard Zinc. Cancerous Ones Don’t.
  Zinc in healthy versus cancerous prostates.
• Vitamin E Supplements Take the Edge Off Endometriosis Pain
  Vitamin E supplements eased endometriosis pain.