What is the minimum recommended intake of α-linolenic acid (ALA) for women and men?
1.1g for women and 1.6g for men
Which hormones stimulate lipolysis?
Epinephrine, norepinephrine, adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), glucagon, growth hormone, and thyroxine (T4)
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Essential Fatty Acids

What is the minimum recommended intake of α-linolenic acid (ALA) for women and men?

1.1g for women and 1.6g for men

Hormonal Effects of Dietary Fat

Which hormones stimulate lipolysis?

Epinephrine, norepinephrine, adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), glucagon, growth hormone, and thyroxine (T4)

Fatty Acid Classification

What are the three most common types of fatty acids?

Saturated (SFA), Monounsaturated (MUFA), and Polyunsaturated (PUFA)

Cholesterol and Lipoproteins

What is the primary function of LDL cholesterol?

To transport cholesterol to tissues where it may be used for membrane construction or conversion into other metabolites

Dietary Fat Intake Recommendations

What is the recommended minimum fat intake for good hormonal health and performance?

At least 20% of total energy intake

Triglycerides and Body Fat Storage

What percentage of dietary fat is stored in the form of triglycerides?

95%

What are the simple lipids?

<ol class="tight" data-tight="true"><li><p>Fatty acids</p></li><li><p>Triacylglycerols</p></li><li><p>Diacylglycerols</p></li><li><p>Monoacylglycerolds</p></li><li><p>Waxes (esters of fatty acids)</p></li></ol><p></p>

Essential Fatty Acids

What are the two essential fatty acids that must be obtained through diet?

Linoleic acid (LA) and α-linolenic acid (ALA)

Cholesterol and Lipoproteins

What is the primary function of HDL cholesterol?

<p>To reverse cholesterol transport by collecting cholesterol from tissues and blood and transporting it to the liver for excretion. HDL is basically the cholesterol clean up crew.</p>

Cholesterol and Lipoproteins

What is the recommended intake of dietary cholesterol for muscle growth and strength development?

At least 7.2 mg dietary cholesterol per kg of lean body mass or more than 400 mg in men

Trans Fat and Health Risks

What is the fourth form of fatty acids that can distort cell membranes and cause inflammation?

Trans fatty acids

Omega-3 Fatty Acids and Benefits

What is the recommended daily intake of combined EPA and DHA for athletes?

Over 2g combined EPA + DHA per day

Omega-3 Fatty Acids and Benefits

What are the three major omega-3 fatty acids?

EPA, DHA, and ALA

Trans Fat and Health Risks

What are some health risks associated with trans fatty acid consumption?

Diabetes, brain and heart toxicity, infertility, coronary heart disease, depression, and Alzheimer’s disease

Essential Fatty Acids

What is the minimum recommended intake of linoleic acid (LA) for women and men?

12g for women and 17g for men

Fat Metabolism and Digestion

What is the process called when fats are broken down for energy?

Lipolysis

Omega-3 Fatty Acids and Benefits

What is the preferred omega-6 to omega-3 ratio?

Closer to 1:1 but no more than 4:1

What can trans fat do to the body?

<ol class="tight" data-tight="true"><li><p>Cause inflammation</p></li><li><p>Increase LDL cholesterol levels</p></li><li><p>Decrease HDL cholesterol levels</p></li><li><p>Distort cell membranes</p></li></ol><p></p>

Why are PUFAs, and not SFA or MUFAs, more likely to be converted into trans fat?

<p>PUFAs have multiple double carbon bonds which are at risk of converting to trans fat when processed at high temperatures for a substantial amount of time. SFAs do not have any double carbon bonds so they are not at risk of being converted to trans fat. MUFAs only have a single double carbon bond so the risk of converting to trans fat is very minimal.</p>

What is the minimum RDI (in both percentage and absolute terms) for individuals to ensure adequate vitamin absorption and to cover essential fatty acid requirements?

<p>10-15% of total daily kcal<br>Absolute minimum of 20 g for women and 30 g for men<br>Over 20% or 44-56 g is generally advisable</p>

What are the compound lipids?

<ol class="tight" data-tight="true"><li><p>Phospholipids</p></li><li><p>Glycolipids</p></li><li><p>Lipoproteins</p></li></ol><p></p>

How could a high fat intake increase muscle mass without acutely improving protein balance?

<p>An increased fat intake can improve the endogenous production of anabolic hormones and also possibly by alter muscle cell membrane functioning.</p>

Why could women benefit from a higher fat intake than men?

<p>Women’s metabolisms are more protein- and glucose-sparing than men’s in comparison and so they preferentially oxidize fat for fuel/energy (fat is the generally preferred energy substrate). Dietary fat can also be more satiating in women than men. An increase in dietary fat can also help in greater estrogen production which is beneficial for women.</p>

How is it possible that differences in testosterone levels between individuals do not correlate with muscle mass but differences within individuals do?

<p>It is not how much testosterone per se that someone has but rather the amount of androgen receptors which predicts how much muscle mass someone can gain. An individual can have as much testosterone as someone else, but if the other person has more androgen receptors, then that individual likely has a greater propensity for building for muscle. The other person may also have a stronger affinity for the receptor, a higher amount of unbound testosterone, or less antagonistic activity on the androgen receptor.</p>

How could androgenic-anabolic steroid users thrive on a low-fat diet that is problematic for a natural trainee to follow?

<p>AAS users do not benefit from anabolic hormonal benefits that increased fat intake provides to natural trainees as they are already providing themselves with amounts of exogenous testosterone that are above and beyond what the body can produce naturally.</p>

Before fats can be ________, they first have to be ________ and then ________.

<p>metabolized<br>digested<br>absorbed</p>

Chylomicrons transport ________ lipids whereas VLDLs transport ________ lipids.

<p>exogenous; endogenous</p>

What are chylomicrons?

<p>Chylomicrons are lipoproteins that transport dietary fat metabolites after their digestion and absorption. They are effectively taxi drivers for fats.</p>

Is digestion a limiting factor in how many calories the body can use from fatty foods?

<p>No. The small intestine can digest up to 600 g of triacylglycerols with 95% efficiency.</p>

After digestion, what happens to the short-, medium-, and long-chain fatty acids?

<p>Short- and medium-chain fatty acids are transported directly to the liver from the small intestine.<br><br>Long-chain fatty acids must first be packaged into chylomicrons before being transported to the tissues that need them (e.g., muscle and adipose tissue).</p>

Adipose tissue has ________ that allow it to break down ________ and ________ and absorb the ________ and ________ inside.

<p>lipoprotein lipases<br>chylomicrons<br>VLDLs<br>TAGs<br>cholesterol</p>

Regarding adipose tissue, how is someone's body fat percentage generally determined?

<p>BF% is generally determined by how full a person’s adipocytes are, not the number of adipocytes. After adolescence, the number of adipocytes a person has stays relatively constant and would only materially increase if the person experienced significant fat gain (adipogenesis).</p>

Describe the metabolism of fat storage.

<ol class="tight" data-tight="true"><li><p>Glucose is metabolized to make acetyl-CoA which can be converted to fatty acids.</p></li><li><p>Lipoprotein lipase acts on triacylglycerols (TAG) in chylomicrons and free fatty acids (FFA), diacylglycerols (DAG), and glycerol enter the adipocyte. Glycerol cannot be used and is excreted back into the bloodstream.</p></li><li><p>Lipoprotein lipase acts on VLDLs so TAG, FFA, DAG, monoacylglycerols (MAG), and cholesterol enter the cell.</p></li><li><p>The pathways favor energy storage as TAG. Insulin stimulates lipogenesis by promoting entry of glucose into the adipocyte (cell) and inhibiting the lipoprotein lipase from hydrolyzing the stored TAG into FFA and glycerol.</p></li></ol><p></p>

Describe the liver's role in lipid metabolism.

<ol class="tight" data-tight="true"><li><p>When fatty acids and glycerol are not immediately used for energy or fat storage, they are transported to the liver to be converted into nutrients that are more useful to the body. The liver is the body’s main nutrient repackaging site.</p></li><li><p>In the liver, glycerol can serve as a substrate for glucose via gluconeogenesis or new triglycerides by combining with three fatty acids. </p></li><li><p>The liver can also create its own glycerol and fatty acids.</p></li><li><p>The liver can also convert fatty acids into ketones.</p></li></ol><p></p>

The balance between storing and burning fat is regulated by our ________.

<p>blood glucose levels</p>

How does hyperglycemia and hypoglycemia affect the storage of fat?

<p>Hyperglycemia (high blood sugar levels) triggers the release of insulin which promotes glucose uptake into adipocytes causing lipogenesis to occur instead of lipolysis.<br><br>Hypoglycemia (low blood sugar levels) results in a reduced supply of intracellular glucose which suppresses lipogenesis.</p>

What are the 2 key theoretical benefits for athletes consuming more fat than the generally recommended 10-20%?

<ol class="tight" data-tight="true"><li><p>Increased anabolic hormone production</p></li><li><p>Inherent anabolic effects of certain fatty acids</p></li></ol><p></p>

Testosterone activates the ________, which directly signals the genes in your muscles cells to start producing more protein to grow.

<p>androgen receptor</p>

The magnitude of increase in anabolic hormone levels you can achieve by increasing your dietary fat intake up to ___% of total energy intake may be large enough to have body composition effects.

<p>40</p>

Generally how long does it take for testosterone's effects and benefits to manifest?

<p>weeks and even months</p>

How does testosterone affect muscle growth and strength development?

<p>Testosterone acts on androgen receptors, and this information is passed to the muscle cell cores which give instructions to synthesize muscle proteins (genomic effect). Testosterone also aids in the formation of new satellite cells which contribute to myonuclear addition. Without myonuclear addition (increase in muscle cell nuclei) muscle growth is inherently limited as each nucelus as a limited transcriptional capacity.</p>

What are some general benefits of estrogen from a strength training perspective?

<ol class="tight" data-tight="true"><li><p>Aids in muscle repair</p></li><li><p>Strengthens bones, joints, and connective tissues</p></li><li><p>Anti-catabolic (prevents muscle damage)</p></li><li><p>Decentralizes body fat distribution (improving metabolic health and causing less fat storage around the midsection)</p></li><li><p>Increases metabolism</p></li></ol><p></p>

What are the general benefits of omega-3 fatty acids?

<ol class="tight" data-tight="true"><li><p>Anti-inflammatory</p></li><li><p>Improved total cholesterol levels and slightly raising HDL levels</p></li><li><p>Improvement in insulin resistance</p></li><li><p>Improvement in endothelial function</p></li><li><p>Improvement in depression</p></li><li><p>Improvement in thrombosis (blood clots)</p></li><li><p>Improvement in hypertension</p></li><li><p>Improvement in anti-inflammatory joint pain</p></li></ol><p></p>

For maximum benefits from omega-3 fatty acids, consume ________ of fatty fish per week, or supplement ____ EPA+DHA in the form of fish oil pills.

<p>+700 g; 3 g</p>

What are the effects of omega-3 fatty acids on performance and body composition?

<ol class="tight" data-tight="true"><li><p>Lower chronic inflammation levels - which improves acute inflammation signaling to repair damage muscles after training</p></li><li><p>Protect against excessive muscle damage and improve neuromuscular recovery</p></li><li><p>Lower cortisol levels, reducing catabolic activity and improving nutrient partitioning</p></li><li><p>Increase testosterone production</p></li><li><p>Increase anabolic signaling and MPS after meals</p></li><li><p>Increase fat oxidation rates and metabolism by increasing MPS rates and LBM</p></li></ol><p></p>

The ________ is the central site of cholesterol metabolism as it is responsible for the creation of ________ which transport the cholesterol.

<p>liver<br>lipoproteins</p>

Why is LDL cholesterol commonly known as "bad cholesterol" and why is this a misnomer?

<p>LDL cholesterol is seen as bad due to the capacity of its load of cholesterol and other lipids to clog up your blood vessels. However, LDLs are vital for lipid metabolism in the body. LDLs are just lipid transporters in the body so they are not inherently unhealthy. </p>

How can LDLs cause problems?

<ol class="tight" data-tight="true"><li><p>LDLs can break or get stuck in our blood vessels, causing cholesterol to clog up the blood vessel.</p></li><li><p>Over time, excessive cholesterol accumulation can cause plaque to build up which narrows the blood vessel and obstructs blood flow.</p></li><li><p>Cholesterol getting stuck in our arteries in the primary cause of cardiovascular disease.</p></li><li><p>When lipids enter our arterial wall, they form plaque which obstructs blood flow - this process is called atherosclerosis.</p></li></ol><p></p>

Of all cholesterol numbers, ________ is the best measure of cardiovascular risk.

<p>the total apolipoprotein B (ApoB) particle number</p>

Cholesterol can only get stuck in our arterial walls when in ________.

<p>apolipoprotein B (ApoB)</p>

Why is apolipoprotein B the best measure of cardiovascular risk?

<ol><li><p><span style="color: rgb(255, 255, 255)">ApoB is the primary lipoprotein in chylomicrons, VLDL, IDL, and LDL - each of these has one ApoB particle.</span></p></li><li><p><span style="color: rgb(255, 255, 255)">Total ApoB particle number is a great unified measure for the total non-HDL cholesterol as well as the actual cause of plaque formation.</span></p></li></ol><p></p>

Why does dietary cholesterol not have much, if any, effect on most people's blood (serum) cholesterol levels?

<p><span style="color: rgb(255, 255, 255)">If your diet doesn’t contain much cholesterol, your intestines will increase their absorption to compensate. If that is not enough, your body will produce its own cholesterol. If your diet contains excessive amounts of cholesterol: (i) your body will reduce its absorption, (ii) the liver will decrease its synthesis, and (iii) the cholesterol excretion rate increases. Therefore, for most people, how much cholesterol you eat doesn’t have much effect on how much cholesterol in your blood.</span></p><p></p>

Study Smarter, Not Harder
Study Smarter, Not Harder