Mindset: Why Your All-or-Nothing Diet Mentality Is Holding You Back
Especially in your 30s and 40s
Imagine This
You're 38, juggling work, family, and personal aspirations. You've tried every diet—keto, paleo, intermittent fasting—and each time, you start with enthusiasm, only to find yourself derailed. The all-or-nothing mindset follows: "I ate one cookie; I might as well finish the box." This cycle of perfectionism and guilt isn't just emotionally draining; it hinders long-term health and weight management.
Sound familiar? Keep reading to learn more about why it happens and what you can do.
The Science Behind the ‘All-or-Nothing’ Mentality
Cognitive Distortions and Dieting
What we often refer to as “all-or-nothing” thinking is an example of cognitive distortion—a pattern of thought that reinforces negative emotions and behaviors. The keyword here? REINFORCES. This is why it can be such a tricky habit to break free of, your brain wants to justify your actions.
In the realm of dieting, this often manifests as labeling foods as "good" or "bad". This ultimately becomes a label you put on YOURSELF. You determine, I am “good” or I am “bad” based on how well you stuck to your plan.
In my practice, foods often labeled as “bad” aren’t always the obvious offenders (such as Twinkies, candy, and soda). With influencers screaming about heavy metals, the “harmful” effects of vegetable oils, gluten and dairy avoidance for everyone, and the dangers of sugar, it can feel confusing knowing what is actually “good” these days.
While at the surface, it may seem like dietary restrictions can support weight loss or health-related goals, that’s not always the case. Research indicates that “black and white” thinking (referred to as dichotomous thinking) can actually lead to overeating and weight gain. This is because people tend to abandon their diet after a perceived failure. Sometimes for good, and sometimes they come back and diet HARDER, as a way to make up for their perceived failure.
*If you’re avoiding gluten or dairy because you notice improvements without them or have an allergy, this is very different than avoiding a food group because you heard it may be “bad” for you. (Always do your own research, and see if certain diet changes makes sense for YOU.)
Metabolic Implications of Extreme Dieting
Yo-yo dieting isn’t just tough on your ego and confidence, it can impact your physical health and metabolism. Significant caloric restriction and frequent weight fluctuations can negatively impact your metabolic rate, making it harder to lose weight and easier to gain it back. It also tells your body it’s essential “unsafe” or “uncertain” of how much you’ll eat in the future. This can increase your overall stress levels, which doesn’t help anyone.
In mid-life, hormonal changes, particularly a decline in estrogen and progesterone, impaired thyroid function (not everyone, but common in many), and decreased insulin sensitivity, can exacerbate these effects.
This is especially true if you’re going hard on a low-carb/keto diet for an extended period of time, and then decide to increase carbs. Your body can become adapted to a certain style of eating, and it takes time to recalibrate back to metabolizing carbs efficiently.
The Benefits of a Flexible Approach
Flexible Restraint and Weight Loss
Adopting a flexible approach to eating, known as "flexible restraint" in research, involves setting guidelines without rigid rules. Studies have shown that individuals who practice flexible restraint are more successful in maintaining weight loss over time.
What does this look like in practice?
Enjoying pizza night with your family, but maybe having 1-2 slices with a side salad vs 1/2 the pizza.
Enjoying a dessert with your kids, but opting for a few bites or a small serving.
Eating protein- and fiber-rich foods before having something more processed.
Being content with “good enough” when you’re at social events or traveling.
Tracking your intake using a food scale for a short period of time to understand portion sizes to hit your goals, and then implementing a more mindful approach without calculations.
Psychological Well-being
Flexibile dieting is also associated with improved psychological well-being. This makes sense, right? White knuckling and perfectionism with food is no way to live. Flexibility with foods allows you to be human, while also having goals.
I’ve noticed some women slip into a cycle where they become obsessed with only choosing clean options, in the spirit of being healthy, which negatively impacts their relationship with food.
If you struggle to eat outside your home even on the rare occassion, when you don’t know what ingredients or sourcing is used, it may be time to loosen the reins. Not everything you eat has to be organic, grass-fed, and single ingredient to be considered “healthy” and support your goals.
How to Break the All-or-Nothing Cycle
1. Reframe Your Mindset
Instead of viewing a single indulgence as a failure, reframe it as a part of a balanced lifestyle. Understand that one cookie or missed workout doesn't negate your progress; it's the overall pattern that matters.
Action: Get curious about why the indulgence happened and what you could do differently the next time. Did you view the treat/food as “bad” and eat it quickly so the package was gone? Did you not eat enough earlier in the day, so your hunger cues were overpowering? Did you eat the food too quickly, and lost the ability to tap into your feelings of fullness?
2. Implement the 90/10 Rule
Aim to make healthy choices 90% of the time, allowing for flexibility in the remaining 10%. While some approaches aim for 80/20, and this may work for some, I find that body composition results in perimenopause can require more than 80% effort. This freedom and budget for treats reduce feelings of deprivation and support long-term adherence to healthy habits.
Action: Reassess if you need to be on a specific diet, or if something like macro tracking (allowing flexibility with objectivity to hit your goals) or even simply focusing on the foundations makes the most sense for you in this season.
3. Question Your Beliefs
Sometimes we pick up on dietary patterns or restrictions from experts or influencers without conciously asking if it makes sense for us.
Action: Ask yourself if you really need to avoid X,Y,Z food. Where did you hear that from and how do you know FOR SURe it makes sense for you? Would your life be easier or more enjoyable with that food occasionally in your plan?
4. Practice Mindful Eating
While the 10-20% allows for freedom, you still need to pay attention to hunger and fullness cues, and savor each bite. 10% doesn’t mean polishing off the container and calling it good because it fits within your budget. This is one of the biggest mistakes I see people make when they implement a macro based approach. More processed forms of protein and carbohydrates don’t lead to the same level of satiety as more whole foods versions (protein bars vs lean meat or whole potatoes vs chips).
Mindful eating can help prevent overeating and foster a healthier relationship with food. And remember, it’s a practice, not something that’s done overnight.
Client Success Stories
Sarah's Transformation
Sarah, a 40-year-old mother of two, had long struggled with the all-or-nothing mentality after following a Paleo-style diet for years. It was mentally difficult for her to allow dairy into her diet after years of unnecessarily avoiding it due to the Paleo diet “rules” and believing it was “bad”. After embracing a flexible approach to eating and incorporating strength training into her routine, she not only lost weight but also experienced improved energy levels and a more positive relationship with food. It was much easier for her to hit her protein goals by adding Greek yogurt and cottage cheese, and she enjoyed the ability to have ice cream out with her family during the summer.
Julie’s Journey
Julie, 32, had been yo-yo dieting for years. She tried nearly every diet out there, but was frustrated by her inability to consistently follow the diet’s rules. She leaned heavily into the foundations (prioritizing whole foods, high protein, fiber, and hydration) in lieu of diet rules. She started thinking about food less (less food noise) and was more social because she didn’t have to work as hard to be “compliant.” Because she focused on the foundations, she didn’t find herself binging as often after she “fell off the wagon”. She released weight that her body had been holding onto for the last 5 years.
Your Thoughts
Have you ever found yourself stuck in an all-or-nothing mindset when it comes to nutrition or exercise? I'd love to hear your thoughts and experiences!
"A weight loss and maintenance intervention in overweight women: the role of restraint and disinhibition" https://pubmed.ncbi.nlm.nih.gov/29494790/
"Eating behavior change and improved psychological health during weight loss interventions in overweight adults" https://pubmed.ncbi.nlm.nih.gov/24854807/
I so needed to read this today - and even read it for a second time! Thank you for this great and timely post.