It’s the End for Splenda and Aspartame for Long Term Health - Dr. Nick Norwitz

Artificial Sweeteners and Metabolic Effects

• Artificial sweeteners are a heterogeneous group of molecules with unique effects in different metabolic contexts, requiring individual study rather than generalization based on being natural or artificial (42s).
• A randomized control trial published in Sellers Metabolism in 2020 found that a combination of sucralose and a less sweet sugar caused profound insulin resistance in adults and adolescents, whereas pure sucralose did not have the same effect (2m8s).
• The study's findings contradict the "uncoupling hypothesis," which suggests that the body will experience metabolic dysfunction when it tastes sweetness without receiving calories (1m43s).
• The trial involved three groups: one consuming a sugar drink, one consuming a sugar drink with sucralose, and one consuming a pure sucralose drink, with the combination group showing the most significant negative metabolic effects (2m5s).
• The substudy in adolescents was terminated early due to the profound effects on insulin resistance, highlighting the importance of context in understanding the metabolic effects of artificial sweeteners (2m31s).
• The study's results imply that consuming a reasonable dose of sucralose, such as two and a half packets per day, in a context like black coffee may be less metabolically damaging than consuming it in a sweetened yogurt with carbohydrates (3m7s).
• The importance of context in understanding the metabolic effects of artificial sweeteners is emphasized, as the same sweetener can have different effects in different situations (2m50s).

Thrive Market and Dopamine Reward Circuitry

• Thrive Market is a helpful resource for grocery shopping, allowing users to search for specific dietary needs such as gluten-free, Paleo, sugar-free, and keto, with a 30% off discount link available for entire grocery orders (3m50s).
• A study found changes in dopamine reward circuitry in the brain, specifically in the meso-limbic areas, when combining carbs and a sweetener, raising questions about the relationship between insulin resistance and dopamine circuitries (4m42s).
• The study used functional magnetic resonance imaging (fMRI) to observe changes in the brain, and the findings opened up questions about the underlying mechanisms of the changes, including whether it's a bottom-up or top-down process (4m44s).
• The study also included an adolescent sub-study, which found that teenagers have physiologic insulin resistance, and the researchers wondered if the changes in the brain's dopamine circuitry could affect peripheral insulin resistance (5m20s).
• The study's findings raise questions about the potential long-term effects of consuming sucralose, particularly in adolescents, and whether it could prime their brain for metabolic dysfunction in adulthood (5m41s).
• The data from the study do not provide clear answers to these questions, but it is essential to consider the unknowns and potential risks when deciding what to consume daily (6m22s).
• The study's findings are intriguing, and it is unclear whether the negative effects of combining sucrose with sugar are due to the calories being ingested or the specific combination of sucrose and sugar (6m34s).
• The study did not present a clear biological explanation for the findings, and it is likely that follow-up studies will be conducted to further investigate the effects of sucralose (7m4s).

Aspartame and Sucralose: Long-Term Health Effects

• The discussion revolves around the effects of artificial sweeteners, specifically aspartame and sucralose, on long-term health, with a focus on their potential to cause anxiety and mood disturbances (7m48s).
• Aspartame has been shown to be problematic in studies, with a biological possibility of breaking down and changing neurotransmitter precursors in the brain, leading to anxiety phenotypes and mood disturbances (8m32s).
• A study published in the Proceedings of the National Academy of Sciences in 2022 found that aspartame can produce an anxiety phenotype in rodents, which can be inherited by their offspring even if they have never been exposed to aspartame (9m23s).
• The study used a dose equivalent to a human drinking two to four Diet Cokes per day, which is within the tolerable limit proposed by the FDA, and found that the offspring of rodents exposed to aspartame had an anxiety phenotype (10m7s).
• The study's findings suggest that aspartame may have a lasting impact on health, not just for the individual consuming it, but also for their offspring, raising questions about the cost of giving up aspartame in favor of alternative sweeteners or beverages (11m8s).
• Sucralose is also considered problematic, but the speaker notes that they have consumed it in the form of KetoChow while in medical school, breaking their own rules (8m14s).
• The speaker emphasizes that both aspartame and sucralose are problematic and should be avoided, but acknowledges that sometimes it is necessary to make exceptions (8m12s).
• The discussion highlights the importance of considering the potential long-term effects of artificial sweeteners on health and the need for further research in this area (9m2s).

Informed Choices and Individual Decisions

• Randomized control trials on humans cannot be conducted to demonstrate the effects of certain sweeteners, but existing data on sperm epigenetics is enough to motivate behavior change in one's life (11m25s).
• The decision to consume sweeteners like sucrose or aspartame should be based on informed choices, considering the potential consequences, and adults should be able to make their own decisions (11m53s).
• Sweeteners are complex, heterogeneous molecules with complex effects, and discussing each one in different contexts is necessary for people to make informed decisions (12m11s).
• If someone loses weight using a sweetener like sucrose or aspartame as a tool and then gets pregnant, it may be a good trade-off for their metabolic health, even considering the potential effects on their offspring (13m29s).
• The use of diet coke or similar sweeteners as a necessary tool for weight loss should be evaluated on an individual basis, and people should consider the literature and potential consequences before making a decision (13m41s).
• Oversimplifying the effects of sweeteners, such as assuming they are benign because they are no-calorie or artificial, is not helpful and does not allow people to make informed decisions (14m8s).

Stevia and Other Sweeteners

• Stevia has been making headlines, and there are questions about its potential effects, including the possibility of getting hooked on something sweet and transferring that to other cravings (14m27s).
• Consuming concentrated sweeteners like Stevia may potentially lead to problems, including a dopamine perspective, where one becomes almost hooked on something sweet (14m41s).
• Consuming artificially or naturally sweetened things can lead to a dopamine hit, making some people feel like they're filling a void or seeking a reward, and this effect may vary from person to person (15m12s).
• Some people may find that using sweeteners, whether artificial or natural, helps them maintain their lifestyle, while others may find it triggers a desire for more sweet things and leads to falling off their diet (15m42s).
• Stevia is considered neutral and benign metabolically, with some studies showing it has little to no effect on insulin response or other metabolic factors (16m10s).
• A recent study comparing Stevia to allulose, a rare sugar and low-calorie sweetener, found that Stevia was benign, but allulose had advantages, including protecting against Western diet-induced obesity in mice (16m46s).
• Some low-calorie sweeteners may have positive metabolic benefits, such as direct effects on fat cells or effects on GLP-1, although more research is needed to confirm these findings (17m36s).

Sucrose and the Microbiome

• The effect of sucrose on the microbiome is an area of ongoing research, and while it's complex, it's worth considering and studying further to understand its potential impact on health (18m24s).
• Research by the Whitesman group has explored the effects of sucrose on the microbiome, highlighting the need for more research in this area (18m44s).
• A study published in Nature in 2014, led by senior author Aaron Sessler, investigated the effects of artificial sweeteners on the microbiome, including aspartame, sucralose, and saccharine, with a focus on saccharine, and found that these sweeteners can cause insulin resistance in humans and mice (18m54s).
• The researchers used a fecal transplant experiment to show that the microbiome of humans who consumed artificial sweeteners and became insulin resistant could confer insulin resistance to mice, demonstrating a causal link between artificial sweetener consumption and insulin resistance (19m31s).
• The study found that some humans were "responders" who became insulin resistant after consuming artificial sweeteners, while others were not, suggesting that individual differences in the baseline microbiome composition may play a role in susceptibility to the negative effects of artificial sweeteners (19m53s).
• The study's findings suggest that artificial sweeteners can disrupt the microbiome and lead to negative metabolic consequences, and that individual tolerance to these effects may vary (20m24s).
• The results of the study are considered relevant and worthy of consideration, and individuals may want to take a pause and reassess their consumption of artificial sweeteners, especially if they are not necessary for their lifestyle (21m2s).
• Some people may rely on artificial sweeteners as a tool to make healthier choices, while others may consume them out of habit, and it may be worth considering alternative options or removing them from one's diet (21m29s).

Artificial Sweeteners vs. Regular Sugar

• Comparing artificial sweeteners to regular sugar is not always a fair comparison, as individuals who consume artificial sweeteners may not necessarily switch to regular sugar if they stop consuming artificial sweeteners (21m55s).
• Many people would choose a sugar-free option like Diet Coke over regular Coke due to its zero calories, especially those who are concerned about their weight or are trying to manage their calorie intake (22m16s).
• However, it's observed that many overweight people drink diet soda, while thinner people tend to drink regular soda, although this doesn't necessarily mean that diet soda causes weight gain or regular soda causes weight loss (22m44s).
• A safer alternative to both regular and diet soda could be a stevia-sweetened beverage like Zia, which is considered a better choice based on available literature (23m27s).
• When people are informed about the potential risks and benefits of different sweeteners, they can make more informed decisions about their health and take steps to improve their metabolic health (23m40s).
• It's not necessary to make all changes at once; people can start by cutting out sugar and using diet soda as a tool, then gradually transition to healthier options like Zia or sparkling water (24m4s).
• Metabolic health is accessible to everyone, and people can experiment and observe the effects of different choices on their own bodies, which can be a privilege and a key to unlocking good metabolic health (24m25s).

Dr. Nick Norwitz

• Dr. Nick Norwitz can be found on social media platforms, where he shares information and insights about metabolic health and wellness (25m1s).