Browse the evidence

During total starvation, fat loss is significantly reduced (averaging 75 g/day) and lean tissue loss is significantly increased (averaging 576 g/day) compared to caloric restriction (fat loss 553 g/day, lean loss 224 g/day).

If your goal is to lose fat while keeping muscle, do not fast completely. This 1967 study found that a moderate 800-calorie diet burned fat 7 times faster than total starvation, while total starvation caused 2.5 times more muscle loss. Rapid weight loss on a fast is mostly water and tissue breakdown, not fat.

A low-carbohydrate, high-fat diet may increase low-density lipoprotein cholesterol (LDLc) levels, which is a potential adverse effect compared to a control diet.

Be aware that switching to a low-carb, high-fat diet might increase your LDL cholesterol levels. However, this should be viewed in the context of improved triglycerides and HDL, which are better predictors of heart disease risk. Consult a healthcare provider if you have a history of lipid disorders.

Acute weight loss or fasting triggers a transient, physiological influx of macrophages into adipose tissue to clear lipid droplets from dead adipocytes, which is a healthy adaptive response distinct from chronic pathological inflammation.

When you lose weight rapidly, your body temporarily sends immune cells to clean up dead fat cells. This causes a short-term spike in inflammation markers, but it is a normal, healthy part of the process, not a sign of damage.

There is insufficient evidence to set an upper limit for added sugar intake based on health risks such as dental caries, weight gain, or metabolic effects.

EFSA does not set a specific upper limit for added sugars due to insufficient evidence, but notes that frequent consumption increases dental caries risk. Focus on oral hygiene and balanced diets.

High intake of saturated fatty acids (SFA) and low intake of polyunsaturated fatty acids (PUFA) in non-obese, non-diabetic NASH patients are directly associated with reduced insulin sensitivity and impaired postprandial triglyceride clearance.

If you have NASH, focusing solely on weight loss or total calorie counting may not be enough. Prioritize reducing saturated fats (found in red meat, full-fat dairy) and increasing polyunsaturated fats (found in fish, nuts, seeds) and fiber. This shift in fat quality is critical for improving insulin sensitivity and clearing triglycerides, even if your weight remains stable.

In North America, living in low-income or minority neighborhoods is associated with constrained access to supermarkets and higher prices for healthy foods, which contributes to higher obesity rates; this contextual effect is not consistently observed in the UK, Australia, or the Netherlands.

If you live in the US or Canada, your neighborhood's lack of healthy food options and higher prices may be a significant barrier to healthy eating, contributing to weight gain. However, if you live in the UK, Australia, or similar regions, simply moving to an area with more supermarkets may not solve obesity issues, as studies show no consistent link between store proximity and diet quality there. Focus on individual dietary choices and physical activity, as environmental constraints may be less decisive in your region.

Fast-food outlets are more prevalent in poorer and minority neighborhoods in North America, and this density is associated with higher obesity rates and cardiovascular outcomes, whereas this association is not consistently found in the UK or Australia.

If you live in an area with many fast-food outlets, you are likely exposed to higher energy-dense foods, which contributes to obesity. This is particularly true in North America. Be aware of your surroundings and try to limit consumption of these high-calorie, low-nutrient foods, even if they are convenient and affordable.

Dietary adherence to national guidelines (≥5 servings of fruits/vegetables daily, <30% calories from fat, <10% from saturated fat) is suboptimal in the majority of adults with type 2 diabetes.

Try to eat at least 5 servings of fruits and vegetables daily. Reduce fat intake to less than 30% of total calories and saturated fat to less than 10%. Focus on adding healthy foods rather than just restricting unhealthy ones.

Dysregulation of the gut microbiota (dysbiosis) in the elderly, characterized by decreased diversity and reduced anti-inflammatory bacteria, is a source of chronic low-grade inflammation.

Gut health changes with age, often showing reduced diversity and fewer beneficial bacteria. This dysbiosis is linked to higher levels of inflammatory cytokines. Maintaining gut health through diet may help manage inflammation, although the specific mechanisms are complex.

Curcumin improves lipid profiles and reduces liver fat accumulation in diabetic models.

Curcumin may help reduce liver fat and improve lipid profiles in diabetic individuals, independent of weight loss, according to animal studies.

Increasing dietary fiber intake (4-19 g/day via supplements or whole foods) leads to little to no significant improvement in A1C or CVD risk markers in people with type 2 diabetes, although it may improve postprandial glycemia and inflammatory markers.

Adding fiber supplements (4-19g/day) or eating a high-fiber diet may help with post-meal blood sugar spikes, but it is unlikely to significantly lower your A1C or improve cholesterol levels on its own. Focus on a balanced diet with whole foods rather than relying on supplements for major metabolic improvements.

ATF3 induction by synthetic agents like ST32da promotes adipocyte browning and inhibits lipogenesis, potentially offering a mechanism to combat obesity.

Research indicates that inducing ATF3 expression can help convert white fat to beige/brown fat, which burns energy. A synthetic inducer called ST32da was shown to do this in mice by blocking specific fat-making pathways. This is not yet a available treatment for humans.

Plant-based proteins (excluding soy) have not been adequately studied for their effect on muscle protein synthesis and appetite in aging adults, though soy appears to have similar appetite-suppressing effects to animal proteins.

While soy protein appears to manage appetite similarly to animal protein, there is insufficient evidence for other plant proteins (like peas or oats) in older adults. Prioritize soy or combine plant sources to ensure adequate amino acids, and monitor appetite to prevent unintended weight loss.

High intake of saturated fats and omega-6 fatty acids triggers Toll-like receptor 4 (TLR4) signaling, leading to chronic inflammation, gut barrier breakdown, and immune dysregulation.

Focus on the quality of fats in your diet rather than avoiding fat entirely. High intake of saturated fats (common in Western diets) can trigger immune receptors (TLR4) that lead to inflammation and gut issues. Try to balance your intake by including omega-3 fatty acids, which have anti-inflammatory properties, and be mindful that the source of your fat matters for immune health.

Dietary choices alter the gut microbiome, which in turn affects the development and function of regulatory T-cells (Tregs), influencing the risk of autoimmune and allergic diseases.

Your gut bacteria play a key role in training your immune system. Eating a diet high in fiber and low in processed sugars and saturated fats helps maintain a healthy microbiome, which supports regulatory T-cells that prevent autoimmune and allergic diseases. Probiotics alone are unlikely to fix immune issues if your diet remains unhealthy.

The metabolic benefits associated with Bifidobacterium longum and Faecalibacterium prausnitzii are conditional on dietary intake, specifically disappearing after adjusting for carbohydrate (fiber) and fat intake, respectively.

If you consume probiotics like Bifidobacterium longum or Faecalibacterium prausnitzii, ensure your diet includes adequate dietary fiber and healthy fats. The study suggests these bacteria's metabolic benefits are linked to these macronutrients, so combining them with a fiber-rich, balanced diet may be more effective than the bacteria alone.

Global adherence to the Mediterranean dietary pattern has significantly declined since the 1960s, driven by a disproportionate increase in the availability of non-Mediterranean foods (meat, sugars, vegetable oils) relative to traditional Mediterranean staples.

If you are trying to follow a Mediterranean diet, be aware that global food systems are actively working against you by making non-Mediterranean foods (meat, sugar, refined oils) more available and affordable than traditional staples. To maintain adherence, you must consciously prioritize the availability of Mediterranean foods (olive oil, vegetables, legumes) and limit the intake of the 'western' foods that are increasingly dominating global food supplies.

Decline in mitophagy and autophagy with age leads to the accumulation of damaged mitochondria and ROS, contributing to sarcopenia, neurodegeneration, and cardiovascular decline.

Exercise is a known inducer of autophagy and mitophagy. Maintaining physical activity, especially aerobic and resistance training, may help counteract the age-related decline in these clearance pathways, protecting muscle and brain health.

Gut dysbiosis in obesity increases intestinal permeability, allowing lipopolysaccharide (LPS) to enter circulation, which triggers adipose tissue macrophages to switch from an anti-inflammatory (M2) to a pro-inflammatory (M1) phenotype via TLR4, thereby driving low-grade chronic inflammation.

If you have obesity, your gut health may be driving inflammation. A high-fat or high-sugar diet can damage your gut barrier, letting bacterial toxins (LPS) into your blood. This triggers immune cells in your fat tissue to become pro-inflammatory, worsening insulin resistance and fat storage. Improving gut health through fiber and reducing processed foods may help reduce this inflammation.

Short-chain fatty acids (SCFAs), particularly butyrate, exert anti-inflammatory effects by promoting macrophage polarization to the M2 phenotype and inhibiting NF-κB activation.

Eat more fiber-rich foods (vegetables, whole grains) to feed your gut bacteria. They produce short-chain fatty acids (SCFAs) like butyrate, which help calm inflammation by switching immune cells to a healing (M2) state. This is especially important if you have inflammatory conditions.

European children consume significantly higher proportions of total and added sugars relative to energy intake compared to adults, with sweet products and beverages being the primary sources.

If you are tracking sugar intake for health or weight management, pay close attention to children's diets. They are consuming a disproportionately high amount of sugar, primarily from sweets and sugary drinks, compared to adults. To reduce this, prioritize whole fruits over juices and limit confectionery and sweetened beverages, which are the main drivers of added sugar intake in this demographic.

Higher intake of processed ingredients (PI), such as oils, sugars, and flours, is consistently associated with lower body weight and reduced odds of obesity, whereas ultra-processed food (UPF) intake shows no significant association with body weight markers.

Focus on the type of food rather than just its processing level. This study suggests that diets higher in processed ingredients (like oils, sugars, and flours used in cooking) were associated with lower body weight, while ultra-processed snacks showed no link to weight. Prioritize whole foods for nutrient density, but do not fear basic processed ingredients.

Targeted food taxes on high-saturated-fat items fail to reduce cardiovascular disease mortality because the reduction in saturated fat is offset by a rise in salt consumption due to cross-elasticity of demand.

Simply taxing fat does not guarantee heart health because people switch to other unhealthy options like salty snacks. To be effective, taxes must target specific nutrient combinations (like salt) or use a scoring system (SSCg3d) rather than just fat content, and even then, the impact is modest without broader industry reformulation.

Targeted food taxes based on a nutrient scoring system (SSCg3d) or optimized for best health outcomes can avert 2300-3200 cardiovascular deaths per year in the UK primarily by reducing salt intake.

If governments implement food taxes, they must target specific nutrient profiles (like salt) rather than just fat. A well-designed tax can save thousands of lives by reducing salt intake, even if the percentage change in diet is small.