What is glucagon, and why does it matter for weight loss?
Insulin and glucagon help coordinate whether the body stores or mobilises fuel, and new obesity drugs are making glucagon newly relevant.
What this episode covers
- Most weight-loss talk focuses on insulin, but its partner hormone, glucagon, is getting new attention.
- Glucagon is one of the key hormones that helps keep fuel available when you are not eating: it mainly acts on the liver, telling it to release stored glucose and, in the right conditions, to burn fat and make ketones.
- Because it can raise fat burning and energy use in the liver, some experimental obesity drugs are being designed to add a glucagon effect on top of GLP-1.
- It is a genuinely interesting piece of metabolism, but not a switch most people need to manage themselves.
Confidence in this episode
Everything about how much to believe this episode, in one place.
Established glucagon physiology and early co-agonist trial results are well supported, but the carbohydrate-insulin framing around them and the long-term drug data are not.
- In humans, glucagon acts primarily on the liver, where it promotes glucose production, fat oxidation and ketone production; unlike in rodents, direct effects on fat-cell breakdown appear limited.
- Early trials of investigational drugs that combine GLP-1 with a glucagon effect (not the approved GLP-1 medicines) show added fat loss and improvement in fatty liver.
- Whether carbohydrates and insulin are the main driver of weight gain.
- Long-term safety and results of the newest combination drugs.
Why it matters
Insulin and glucagon are part of the hormonal system that coordinates whether the body stores or uses fuel, but they are not the only things that set body weight. Understanding glucagon helps explain what happens during fasting and why some next-generation obesity drugs are being designed to do more than curb appetite. It is useful background, not a dial most people need to adjust to lose weight.
What stands out
- Glucagon can raise blood sugar, yet researchers are deliberately adding a glucagon effect to some experimental obesity drugs, pairing its effects on liver metabolism and energy use with the appetite and glucose control from incretin drugs.
- In people, glucagon works mainly in the liver, not by pulling fat straight from fat cells, which is what happens in rats.
- Glucagon is not simply a fat-burning hormone: it can raise fat burning and energy use in the liver, but it also raises glucose output, which is why it is studied in combination rather than alone.
Best-supported action
The single highest-leverage move from this episode, anchored in the strongest evidence the speaker presents.
If weight loss is the goal, start with a dietary change that reduces excess energy intake and is sustainable for you; cutting sugary drinks and highly refined foods is a practical first step. A lower-carb pattern or a longer overnight gap may suit some people, but neither is required.
Where to start
Small low-friction starters covering the main moves from this episode.
- Swap one sugary drink a day for water or an unsweetened option.
- Finish dinner earlier to lengthen the overnight gap, if it suits you.
- Read labels for added sugar and refined starch.
- Notice whether frequent snacking is driven by hunger or simply by habit and availability.
Other supported actions
Further actions discussed in this episode, ordered from strongest to weakest evidence. This is one expert's view, the full topic compares and ranks across experts.
- If weight loss is the goal, start with a sustainable change that reduces excess intake; cutting sugary drinks and highly refined foods is a practical first step.Moderate evidence
- A longer overnight eating gap can help some people eat less overall, but it is not required for weight loss or clearly better than other sustainable patterns.Limited evidence
- If weight-loss medication is something you are weighing, treat it as a conversation with a clinician, including how long treatment might last.Moderate evidence
Full context, impact ratings, and timing — available in related topics
Questions to take to your doctor
- Given my weight and blood sugar, would a GLP-1 or newer combination drug meaningfully change my health, and how would we handle diet and muscle while I take it?
- Given my current medications, is a lower-carb pattern or a longer overnight fast safe for me, especially if I take drugs for blood sugar or blood pressure?
Full doctor prep with ranked questions available in the full topic page
Context
BYU metabolic researcher who frames insulin resistance as the connector across multiple cardiometabolic conditions. The insulin-resistance-as-cardiovascular-driver framing is broadly mainstream; the carbohydrate-insulin model as the primary driver of obesity is still actively contested in the energy-balance literature. Bikman has commercial exposure (co-founder of HLTH Code and Insulin IQ, author of Why We Get Sick), which is relevant context when he is the source of a specific protocol or substance recommendation, although it does not itself invalidate the underlying physiology he discusses. Strongest on mechanism; worth pairing with conventional clinical-outcome evidence when the conversation moves from mechanism to recommended daily protocol. In his glucagon lecture he treats low insulin, reached mainly through low-carb eating, as the bigger lever for fat burning than glucagon itself, which is his interpretation rather than established weight-loss guidance.
What this shows: the liver role of glucagon is well supported, and early trials of investigational GLP-1-plus-glucagon drugs show added fat loss and improvement in fatty liver. What it does not show: this is not how the approved GLP-1 medicines work, and the wider idea that carbohydrates and insulin are the main cause of weight gain is still actively debated against energy-balance views. Where evidence is thin: the long-term safety and results of the newest combination drugs are not yet known. Commercial interest: the speaker runs metabolic-health companies and promotes them in this talk, worth knowing when weighing his recommendations, though it does not by itself make the physiology wrong. This does not mean you should start, change, or stop any treatment on your own.
Where people go wrong
- Starting or stopping a prescription weight-loss drug on your own based on a podcast.These are medical decisions, and changing them without your doctor can be unsafe and can waste the benefit.
- Assuming a weight-loss drug is necessarily a short-term fix.Weight regain is common after treatment stops, even when people have changed their habits, because the biology the drug was affecting returns; how long to treat is a question for your doctor.
What to expect over time
- First weeksCutting sugary drinks and highly refined foods can be a practical way to reduce overall energy intake. Early responses vary considerably between people.
- 1 to 3 monthsOver several months, sustainable dietary changes can lead to changes in weight, blood glucose and other metabolic markers, but responses vary substantially between people.
- Long termKeeping weight off is genuinely hard. For some people that means lasting habit change; for others, obesity is a chronic condition that may need ongoing medical treatment, not a willpower fix.