Problems with the milkshake test

In this powerful episode, Dr. Vera Tarman and Clarissa Kennedy welcome back Dr. Nicole Avena, one of the first researchers to scientifically validate the concept of food addiction. Together, they unpack the latest critiques of food addiction and explore why this diagnosis is still being challenged – and why the science strongly supports it.

🔍 Key Questions We Tackled Is food addiction "too broad" to be useful? Can we really rely on self-report tools like the Yale Food Addiction Scale? What about brain imaging – doesn't Kevin Hall's PET study "disprove" food addiction? Are we just pathologizing normal overeating under stress or dieting? If withdrawal from ultra-processed foods isn't like alcohol or opioids, does it "count"?

What Dr. Avena Wants You to Know 1️⃣ Overlap with eating disorders ≠ "not real" Food addiction can overlap with eating disorders and obesity, but that doesn't mean it's the same thing. Lots of conditions share symptoms; that's exactly why we need more research, not less. 2️⃣ Self-report doesn't make it "fake" Critics argue that the Yale Food Addiction Scale (YFAS) isn't valid because it relies on self-report. Dr. Avena reminds us: If we reject self-report, we'd also have to throw out: Depression inventories Alcohol and substance use screens Most mental health assessments we use every day Self-report + clinical judgment + (where possible) biological measures = standard science, not junk science. 3️⃣ One PET scan ≠ "case closed" Kevin Hall's PET study is often waved around as "proof" that food isn't addictive. Dr. Avena explains major limitations: PET is a blunt tool for measuring dopamine compared to methods like microdialysis. The milkshake used was lower in sugar than many people consume in real life. Participants weren't clearly separated into food-addicted vs non–food-addicted groups. Dopamine is highly time-sensitive: anticipation and early consumption may be where the real action is, not 30 minutes later. And importantly: We don't throw out alcohol or nicotine addiction just because a single brain study fails to show a clear dopamine spike. Science is built on many studies over many years, not one headline. 4️⃣ We're not pathologizing everyone who overeats Yes, lots of people overeat on holidays or under stress. That's normal. Food addiction is when: Overeating is persistent and pervasive It causes distress, impairment, and health consequences Multiple DSM substance use criteria are met (tolerance, withdrawal, loss of control, continued use despite harm, etc.) That's a very different picture than "I ate too much at Thanksgiving." 5️⃣ Withdrawal from ultra-processed foods is real (and looks a lot like other addictions) Research now shows that withdrawal from ultra-processed foods can include: Irritability Fatigue Low mood Crankiness / lethargy These symptoms tend to peak in 2–5 days, similar to what we see with substances like nicotine. You don't need seizures for it to count as withdrawal. 6️⃣ Not having a "perfect definition" is not a reason to stop studying it We are still refining: What exactly counts as "food addiction" Which foods / combinations are most addictive How best to diagnose and treat it That's how science works: definition → research → refinement → better definition → repeat. If we'd waited for perfect definitions, we wouldn't have moved forward on half the diseases we now recognize.

💊 GLP-1 Medications & Food Addiction: Clues from Treatment The conversation also touched on GLP-1 medications (like semaglutide and others): For some people, GLP-1s dramatically reduce "food noise" and cravings. For others, they only partially dampen urges – they still need tools, structure, and support. This suggests these drugs are interacting with reward and satiety circuits that are highly relevant to addiction.

Dr. Avena and Clarissa both emphasize: Medication alone is not enough – people still need skills, structure, and support to navigate cravings, emotions, and the food environment.

🧬 Big Picture: Why This Debate Matters Naysayers often publish opinion pieces without new data, recycling old critiques that the research has already addressed. Media then amplifies a single study or opinion as "proof" that food addiction isn't real. Meanwhile, millions of people are struggling in silence, wondering: "If this isn't addiction, what's wrong with me?"

Dr. Avena's message is clear: There is now a large body of evidence – animal, human, behavioral, and neurobiological – supporting food addiction as a valid construct worth recognizing, researching, and treating. ❤️ For Those Who Feel Seen by "Food Addiction" If you've ever felt like: You can't stop with certain foods You eat more than you want, more often than you want You experience cravings, withdrawal, or obsessive food thoughts And you've been told "it's just lack of willpower" or "there's no such thing as food addiction" This episode is for you. You are not making this up. The science is catching up to what lived experience has been saying for decades.